Performance evaluation and emission characteristics of biodiesel-ignition enhancer blends propelled in a research diesel engine

This study details the effect of the Di-Methyl-Ether(DME) as a cetane improver on neat cashew nut shell biodiesel (CBD100) to assess the emission and performance engine characteristics. Four fuels, namely, diesel, biodiesel (Cashew nut shell Methyl Ester), a blend of CBD100-10% and 20% by volume of DME (CBD90DME10and CBD80DME20) are prepared and tested on a stationary research diesel engine. The experimental parameters for CBD80DME20 showed a 1.6% increase in thermal efficiency thereby reducing 4.1% of fuel consumption than the neat biodiesel at peak conditions. Experimental result exposed that 20% of DME reduces 3.4% CO, 4.2% HC and 8.8% NOx and 8.4% smoke emissions of CBD100. Based on the outcome of this work, it is clear that CBD80DME20 shall be employed as a substitute fuel for diesel engine.

Abbreviations: CI: Compression ignition; CBD100: Cashew nut shell Bio-diesel; DME: Di-methyl ether; CO: Carbon monoxide; BTE: Brake thermal efficiency; BSFC: Brake specific fuel consumption; CBD100: 100% Biodiesel; CBD90DME10: 90% biodiesel + 10% di-methyl-ether; CBD80DME20: 80% biodiesel + 20% di-methyl-ether; HC: Hydrocarbon; NO_x: Oxides of nitrogen.     

板栗内皮对水溶液中镉的吸附研究

采用生物吸附法去除水体重金属污染具有重要的现实意义.本文以板栗内皮为吸附剂,研究了溶液pH值、反应时间、吸附剂投加量对水溶液中镉的吸附量与去除率的影响;通过模型拟合、离子交换实验、电镜扫描（SEM）和红外光谱（FTIR）分析,对吸附机理进行了探讨.结果表明：板栗内皮是一种理想的镉吸附剂,适应pH值范围宽（3～6）,达到...     

天津滨海贝壳堤成因与海岸线的演变

本文通过对天津滨海贝壳堤成因的研究,初步确定贝壳堤是全新世晚期形成的,它的形成和演化反映了近岸生源物质迁移、现代沉积过程,贝壳堤的演化模式划分为三个阶段.这对正确地揭示淤泥质平原海岸的形成机理、合理规划开发潮滩和贝壳堤资源有着重要意义.     

Copper(II) ions’ removal from aqueous solution using green horse-chestnut shell as a low-cost adsorbent

The adsorption of copper(II) ions from aqueous solutions by the green horse-chestnut shell was studied in a batch adsorption system. It was determined how the parameters of the adsorption process, such as time, pH, copper(II) ions concentration and sorbent dose, influence the effectiveness of copper(II) ions’ removal. The adsorption process was fast and equilibrium was established about 10?min, and near 95–97% of Cu(II) ions were removed from aqueous solution. Maximum copper(II) ions’ adsorption occurred at around pH 5. The adsorption kinetics are also described, using pseudo-first-order model and pseudo-second-order model of type 1 and 2. A comparison of the kinetics models on the overall adsorption rate showed that the adsorption system was best described by the pseudo-second-order model of type 1 (r²?=?0.999) for all initial concentrations. Another key part of this study was the use of the Freundlich model to determine the adsorption isotherm and the experimental data were in strong correspondence with this model.     

改性花生壳对Cd(Ⅱ)和Pb(Ⅱ)的吸附机理

以前期制得改性块状花生壳为对象,测定改性花生壳等电点,考察离子强度对改性花生壳吸附Cd2+和Pb2+的影响、吸附前后吸附质溶液pH变化情况及蒸馏水、NaCl、HNO3、柠檬酸和EDTA 5种解吸液对Cd2+和Pb2+的解吸效果,并通过X-射线光电子能谱仪和傅里叶变换红外光谱仪对吸附前后的改性花生壳进行表征,推测并证实了改性花生壳对Cd2+和Pb2+可能的吸附机理。结果表明,改性花生壳对Cd2+和Pb2+可能的吸附机理是:Cd2+是通过外层络合、离子交换和内层络合的联合作用被吸附的;Pb2+主要是与改性花生壳上的O、N等活性基团发生内层络合;此外,改性花生壳表面生成的二氧化锰对Cd2+和Pb2+的吸附也起到一定的作用。     

新型污泥脱水絮凝剂的研制

以累托石和虾蟹壳为主要原料,制备出一种新型污泥脱水絮凝剂。研究了该絮凝剂的制备工艺条件,探讨了该絮凝剂的絮凝机理。该絮凝剂的最佳配方为：天然有机高分子材料与改性累托石质量比1：6,将其配制成质量分数为1％的絮凝剂工作液,处理污泥的最佳加入量为1mL／L,最佳沉降时间为20min。与传统絮凝剂聚丙烯酰胺相比,污泥脱水率提高了5．47％,污泥沉降时间缩短了33．33％,吨污泥单耗絮凝剂成本下降了4％,且处理过程中的二次污染大幅度减小。     

Distribution of organophosphate insecticides in a Thai biomass-water system

Sorption and leaching of the organophosphate (OP) pesticides chlorpyrifos, profenofos, methyl parathion and malathion were investigated with four different types of biomass: coconut husk, rice husk, peat moss and peanut shell. Organic carbon contents of the biomass were in the range of 35.4–45.4%. Sorption studies were carried out by the batch (equilibrium) method at 4 different OP spike concentrations and at pH 3–7. Sorption isotherms conformed to a linear Freundlich equation and the Freundlich constant or sorption coefficient (K_D) confirmed that biomass organic carbon content was the principal sorbent factor affecting OP sorption. For a given sorbent, correlation of the extent of sorption with sorbate chemical properties was examined. Column leaching experiments involving different masses of coconut husk and peanut shell pre-spiked with OPs at the level equivalent to actual spraying concentrations in some Thai tangerine orchards were conducted. These experiments included repeated spikings and leaching. A water flow rate of 20 mL min^?1 was employed corresponding to the current average watering regime. Retardation and biodegradation with these sorbents were also examined.     

Effects of mussel shell addition on the chemical and biological properties of a Cambisol

The use of a by-product of the fisheries industry (mussel shell) combined with cattle slurry was evaluated as soil amendment, with special attention to the biological component of soil. A wide number of properties related to soil quality were measured: microbial biomass, soil respiration, net N mineralization, dissolved organic carbon, dissolved organic nitrogen, dissolved inorganic nitrogen, dehydrogenase, β-glucosidase, urease and phosphomonoesterase activities. The amendments showed an enhancement of soil biological activity and a decrease of aluminium held in the cation exchange complex. No adverse effects were observed on soil properties. Given that mussel shells are produced in coastal areas as a by-product and have to be managed as a waste and the fertility constraints in the local soils due to their low pH, our research suggest that there is an opportunity for disposing a residue into the soil and improving soil fertility.     

长柄扁桃核壳活性炭的制备及表征

以长柄扁桃核壳为原料采用磷酸活化法制备活性炭,分别研究了温度、时间、浸渍比和磷酸浓度对活性炭吸附性能的影响;进而采用氮气吸附曲线和SEM对最佳工艺条件下的活性炭进行了表征。结果表明,长柄扁桃核壳是一种优质的活性炭原料;当温度为400℃,活化时间2 h,浸渍比2：1,磷酸浓度60%时,得到产率为46.46%,碘吸附值和亚甲基蓝吸附值分别为1 073 mg/g、255 mg/g,比表面积高达1 740 m²/g,中孔率为73.12%的孔隙发达的高中孔率活性炭。     

废弃核桃壳粉对模拟微污染水中总铁的静态吸附特性研究

采用废弃核桃壳粉对总铁质量浓度约为3 mg/L的模拟微污染水进行了静态吸附实验研究.结果表明,采用产地为新疆、粒径为1.6～2.5 mm的废弃核桃壳粉1.0 g、水样初始pH为7.0、吸附时间为240 min时,总铁去除率可以达到92.69%.吸附后,水样中总铁浓度满足<生活饮用水卫生标准>(GB 5749-2006)...