Effects of Liquid Crystalline Epoxy Resin on the Properties of Bio-based Cardanol-furfural Resin北大核心CSCD

By using polarized optical microscopy, differential scanning calorimetry, scanning electron microscopy and impact strength measurements,the effects of liquid crystalline on the morphologies, thermal properties and mechanical properties of the composite resins were studied. It was found that the synthesized 4,4-diglycidyloxybiphenyl (BP) and sulfanilamide (SAA) were used to generate novel liquid crystalline (LC) epoxy resins notably. The results revealed that the curing of the cardanol-furfural resins was accelerated and the thermal properties were considerably improved by adding the LC epoxy resins.When the addition of BP-SAA was 50%, the glass transition temperature increased from 60.4 ℃ to 70.2 ℃, and the thermal decomposition temperature increased from 300.3 ℃ to 377.4 ℃, respectively. When the addition of BP-SAA was 30%, the impact strength of the modified resins was 15 kJ/m2 and about three-fold higher than that of the unmodified counterpart. © 2018, Editorial Board of «Chemistry and Industry of Forest Products». All right reserved.     

学术期刊影响因子的应用研究

学术期刊影响因子已经由一种模糊的指标,成为衡量期刊、学术论文、作者、机构等学术研究水平高低的重要的定量测定指标。通过对学术期刊影响因子的使用进行了系统分析,提出影响因子的偏差的负面影响,对如何利用期刊影响因子公正有效的对成果鉴定进行了相关阐述。     

Trend and uncertainty analysis of simulated climate change impacts with multiple GCMs and emission scenarios

Trends and uncertainty of the climate change impacts on hydrology, soil erosion, and wheat production during 2010-2039 at El Reno in central Oklahoma, USA, were evaluated for 12 climate change scenarios projected by four GCMs (CCSR/NIES, CGCM2, CSIRO-Mk2, and HadCM3) under three emissions scenarios (A2, B2, and GGa). Compared with the present climate, overall t-tests (n = 12) show that it is almost certain that mean precipitation will decline by some 6% (>98.5% probability), daily precipitation variance increase by 12% (>99%), and maximum and minimum temperature increase by 1.46 and 1.26 °C (>99%), respectively. Compared with the present climate under the same tillage systems, it is very likely (>90%) that evapotranpiration and long-term soil water storage will decease, but runoff and soil loss will increase despite the projected declines in precipitation. There will be no significant changes in wheat grain yield.Paired t-tests show that daily precipitation variance projected under GGa is greater than those under A2 and B2 (P = 0.1), resulting in greater runoff and soil loss under GGa (P = 0.1). HadCM3 projected greater mean annual precipitation than CGCM2 and CSIRO (P = 0.1). Consequently, greater runoff, grain yield, transpiration, soil evaporation, and soil water storage were simulated for HadCM3 (P = 0.1). The inconsistency among GCMs and differential impact responses between emission scenarios underscore the necessity of using multi-GCMs and multi-emission scenarios for impact assessments. Overall results show that no-till and conservation tillage systems will need to be adopted for better soil and water conservation and environmental protection in the region during the next several decades.     

Re-think urban drainage following a SuDS retrofitting approach against urban flooding: A modelling investigation for an Italian case study

In the last decades, urban sprawl and soil sealing led to an increase of urban flooding phenomena. Sustainable Drainage Systems (SuDS) seem able to weaken stormwater-related criticalities, enhancing sustainability and city resilience.Relying on a detailed and feasible preparatory study of SuDS feasible retrofit design, based on a punctual identification of the areas suitable for retrofitting and the most appropriate combination of SuDS technologies, the reported research aimed to assess the effectiveness of a sustainable drainage approach in Sesto Ulteriano (Italy), an urban catchment suffering from stormwater management concerns. In particular, using the approach of a typical scenario analysis, this comparative modeling analysis involved SWMM5 for the assessment of the differences in the catchment hydrological behaviour between the mentioned specific and feasible SuDS retrofitting scenarios and a potential one, where non-specificity is considered for SuDS retrofitting location. Besides, the analyses focused on investigating how rainfall severity, areal extension and land use typical feature could influence the effectiveness of the sustainable redevelopment of the urban area.Results indicate that SuDS projects based on potential designs, which does not account for the feasible suds location, might result in a significant overestimation of the hydrological benefit. They showed, indeed, an improved hydrological performance, with average total volume reductions of the Combined Sewer Overflows up to over 70 % (retrofitting the 8.3 % of the catchment area), that is about 40 % higher than those obtained under the same areal extension by the feasible scenarios. Moreover, it was found that there could be an optimal SuDS retrofitting percentage above which additional hydrological benefits are undetectable. Land use, resulting in the variability in the degree of imperviousness necessarily associated to a variability in the retrofitting potential, also seemed to affect SuDS hydrological performance and for this reason should be included in an overall assessment. SuDS also proved to act successfully on the actual maximum percentage of nodes of the drainage network above a 0.7 filling degree threshold (about 52 % under 10-year return period rainfall) reducing it to 24 % with a feasible retrofitting involving the 8.3 % of the study area.     

On-farm impacts of zero tillage wheat in South Asia's rice–wheat systems

The recent slow down in productivity growth in the irrigated areas of the Indo-Gangetic Plains of South Asia has led to a quest for resource-conserving technologies that can reduce production costs, save water and improve production. Findings from farm surveys are used to evaluate the on-farm impacts of zero tillage (ZT) wheat in the rice–wheat systems of India's Haryana state and Pakistan's Punjab province. ZT-induced effects primarily apply to the establishment and production costs of the wheat crop. Both study sites confirmed significant ZT-induced resource-saving effects in farmers’ fields in terms of diesel, tractor time and cost savings for wheat cultivation. Water savings are, however, less pronounced than expected from on-farm trial data. It was only in Haryana, India that there were significant ZT-induced water savings in addition to significant yield enhancement. The higher yield and water savings in Haryana, India result in significantly higher water productivity indicators for ZT wheat. In both sites, there are limited implications for the overall wheat crop management, the subsequent rice crop and the rice–wheat system as a whole. The combination of a significant “yield effect” and “cost-saving effect” makes adoption worthwhile and provide a much needed boost to the returns to wheat cultivation in Haryana, India. In Punjab, Pakistan, ZT is primarily a cost-saving technology for wheat cultivation. The prime driver for ZT adoption is not water savings or natural resource conservation but monetary gain in both sites. Water savings are only a potential added benefit.     

土地规划环境影响评价与建设项目环境影响评价的比较

结合国内外环境影响评价研究状况,对土地规划的环境影响评价(LUPEIA)和单个建设项目的环境影响评价(SEA)进行了较为全面的比较,指出了土地规划的环境影响评价与项目环境影响评价的异同,分析了项目环境影响评价对土地规划的环境影响评价的借鉴意义,为进一步开展土地规划的环境影响评价工作提供思路.     

Prospects for Reduced Impact Logging in Central African logging concessions

Reduced Impact Logging (RIL) has traditionally been described as a set of forest management practices that reduce logging impacts and improve productivity. In this paper, we review the evolution of the logging sector in the Congo basin since the early 20th century. We argue that logging in the Congo basin has been little influenced by RIL until the recent regional Forestry Law reforms that started in Cameroon in 1994. RIL has not been integrated into the logging sector of the region as an independent body of knowledge, but more as a complement of the new mandatory management plans. In spite of its proven environmental and economic advantages, the role of RIL in improving forest management has been poorly understood, and we identify some causes of this situation. Finally, based on a regional study of 30 concessions, we analyse the frequency of some RIL-related practices and their relation with markets and certification schemes. We conclude that a clear definition of what RIL techniques are embraced by the logging sector is needed if RIL is to fully benefit from the recent development of new market and logging schemes based on certification, improved logging efficiency and a more transparent chain of custody.     

生态因素和栽培农艺措施对烟草钾和氯含量影响研究进展

钾、氯是烟草生长发育的必需营养元素,也是衡量烟叶内在品质的重要指标,钾氯比值常被用作评价烟叶品质、燃烧性的基础,因此合理调控烟叶钾、氯含量,对改善烟叶品质、提高烟叶质量、提升烟叶工业可用性具有重要意义。探讨了生态因素、栽培农艺措施对烟草钾、氯含量影响的研究进展。     

Schmallenberg virus epidemic: Impact on milk production,reproductive performance and mortality in dairy cattle in the Netherlands and Kleve district,Germany

Schmallenberg virus (SBV), a novel orthobunyavirus that rapidly spread throughout north-western Europe in 2011, caused congenital malformations in lambs and goat kids (Van den Brom et al., 2012) and newborn calves (Hoffmann et al., 2012). The impact of the SBV epidemic seemed limited however, in terms of the number of affected herds with malformed offspring (European Food Safety Authority, 2012b). Nevertheless, little is known with regard to the overall within-herd impact of SBV infection. The objective of the current study was to quantify the impact of the 2011 SBV epidemic on the productivity of dairy cattle in the Netherlands and the district of Kleve, Germany.     

Green composites from maleated castor oil and jute fibres

Castor oil was converted to maleated castor oil (MACO) without any catalyst. MACO was characterized with FTIR, NMR, molecular weight and viscosity measurement. Tung oil (20 wt%) was added to MACO as reactive diluent. Non-woven jute felts were used as reinforcing material. The MACO was polymerized and crosslinked in situ during composite fabrication. The curing behavior of MACO with free radical catalyst was investigated by differential scanning calorimetry (DSC). The MACO/jute composites were tested for their flexural properties, impact strength and dynamic mechanical properties and compared with similar unsaturated polyester resin/jute composites. The flexural moduli of both the composites were nearly similar. The impact strength of MACO/jute composites was 42% higher than that of UPE/jute composites. The damping property of the MACO/jute composites was higher than that of UPE/jute composites over a wide range of temperature.