A Reduced Chemical Kinetic Mechanism for Toluene Reference Fuels Based On DRGEP and QSSA Methods

As a gasoline surrogate fuel, the physical and chemical properties of toluene reference fuel (TRF) are relatively simple and stable, and the TRF chemical kinetic mechanism may be used in simulating combustion processes of gasoline. However, simulations using detailed or semi-detailed mechanisms have been limited due to the computational complexity and long computational time. For the construction of the reduced mechanism, the directed relation graph with error propagation (DRGEP) method is used to wipe out insignificant components efficiently, followed by the use of the quasi-steady state assumption (QSSA) method to separate quasi-steady-state (QSS) species from the kinetic ODEs. In addition, some elementary reactions involving the formation and destruction of H and phenyl methyl radicals are subjected to sensitivity analysis and some kinetic parameters of the relevant elementary reactions are revised. As a result, a reduced mechanism involving 234 reactions and 60 species is developed. Comparing the experimental records with the analog data by utilizing the reduced mechanism, good agreement can be obtained when ignition delay time (τ), laminar flame speed (SL) and molar fraction of vital species are measured. Moreover, the mechanism may predict SL more accurately under lean mixture (equivalence ratio φ < 1.0) conditions. The reduced mechanism is small and reliable in performance, which can commendably reproduce the combustion characteristics of gasoline surrogate

Water management affects arsenic and cadmium accumulation in different rice cultivars

Paddy rice (Oryza sativa L.) is a staple food and one of the major sources of dietary arsenic (As) and cadmium (Cd) in Asia. A field experiment was conducted to investigate the effects of four water management regimes (aerobic, intermittent irrigation, conventional irrigation and flooding) on As and Cd accumulation in seven major rice cultivars grown in Zhejiang province, east China. With increasing irrigation from aerobic to flooded conditions, the soil HCl-extractable As concentrations increased significantly and the HCl-extractable Cd concentrations decreased significantly. These trends were consistent with the As and Cd concentrations in the straw, husk and brown rice. Water management both before and after the full tillering stage affected As and Cd accumulation in the grains. The intermittent and conventional treatments produced higher grain yields than the aerobic and flooded treatments. Cd concentrations in brown rice varied 13.1-40.8 times and As varied 1.75-8.80 times among the four water management regimes. Cd and As accumulation in brown rice varied among the rice cultivars, with Guodao 6 (GD6) was a low Cd but high-As-accumulating cultivar while Indonesia (IR) and Yongyou 9 (YY9) were low As but high-Cd-accumulating cultivars. Brown rice Cd and As concentrations in the 7 cultivars were significantly negatively correlated. The results indicate that As and Cd accumulated in rice grains with opposite trends that were influenced by both water management and rice cultivar. Production of 'safe' rice with respect to As and Cd might be possible by balancing water management and rice cultivar according to the severity of soil pollution.Paddy rice (Oryza sativa L.) is a staple food and one of the major sources of dietary arsenic (As) and cadmium (Cd) in Asia. A field experiment was conducted to investigate the effects of four water management regimes (aerobic, intermittent irrigation, conventional irrigation and flooding) on As and Cd accumulation in seven major rice cultivars grown in Zhejiang province, east China. With increasing irrigation from aerobic to flooded conditions, the soil HCl-extractable As concentrations increased significantly and the HCl-extractable Cd concentrations decreased significantly. These trends were consistent with the As and Cd concentrations in the straw, husk and brown rice. Water management both before and after the full tillering stage affected As and Cd accumulation in the grains. The intermittent and conventional treatments produced higher grain yields than the aerobic and flooded treatments. Cd concentrations in brown rice varied 13.1-40.8 times and As varied 1.75-8.80 times among the four water management regimes. Cd and As accumulation in brown rice varied among the rice cultivars, with Guodao 6 (GD6) was a low Cd but high-As-accumulating cultivar while Indonesia (IR) and Yongyou 9 (YY9) were low As but high-Cd-accumulating cultivars. Brown rice Cd and As concentrations in the 7 cultivars were significantly negatively correlated. The results indicate that As and Cd accumulated in rice grains with opposite trends that were influenced by both water management and rice cultivar. Production of 'safe' rice with respect to As and Cd might be possible by balancing water management and rice cultivar according to the severity of soil pollution

琉璃苣籽油的萃取及对力竭运动大鼠骨骼肌 抗氧化酶活性的影响Extraction of borage seed oil and its effect on antioxidant enzyme activity of skeletal muscle in exhaustive exercise rats

为了促进琉璃苣籽油的开发利用，以琉璃苣籽为原料，采用亚临界丁烷萃取琉璃苣籽油，通过单因素实验研究液料比、萃取温度、萃取时间对琉璃苣籽油萃取率的影响，通过响应面实验对琉璃苣籽油萃取工艺条件进行优化，并对最佳条件下萃取的琉璃苣籽油脂肪酸组成进行分析。将SD大鼠平均分成5组，对照组不进行训练，剩余4组进行力竭运动训练，低、中、高剂量组每日灌胃10、15、20 mg/g琉璃苣籽油，力竭运动组每日灌胃15 mg/g蒸馏水，对照组正常饮水，实验结束后测定大鼠骨骼肌中抗氧化酶活性，考察琉璃苣籽油对力竭运动大鼠骨骼肌抗氧化酶活性的影响。结果表明：琉璃苣籽油最佳萃取工艺条件为液料比6.2∶ 1、萃取温度41 ℃、萃取时间53 min，在该条件下琉璃苣籽油萃取率为35.32%；琉璃苣籽油中不饱和脂肪酸含量为85.51%；琉璃苣籽油可以恢复骨骼肌中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)的活性，降低骨骼肌中丙二醛(MDA)含量。琉璃苣籽油可以提高力竭运动大鼠骨骼肌抗氧化酶活性，提高机体清除自由基的能力，减少对机体细胞的损伤。 In order to promote the development and utilization of borage seed oil, taking borage seed as raw material, the borage seed oil was extracted with the subcritical butane extraction method. The effects of liquid-material ratio, extraction temperature and extraction time on the extraction rate of borage seed oil were studied by single factor experiment. The extraction conditions of borage seed oil were optimized by response surface methodology. The fatty acid composition of the borage seed oil was analyzed. In addition, SD rats were divided into five groups on average. The control group did not receive training, and the remaining four groups received exhaustive exercise training. The low, medium and high dose groups were gavaged with 10, 15 mg/g and 20 mg/g borage seed oil every day, the exhaustive exercise group was gavaged with 15 mg/g distilled water every day, and the control group drank water normally. After the experiment, the activity of antioxidant enzymes in the skeletal muscle of the rats was determined to investigate the effect of borage seed oil on the activity of antioxidant enzymes in the skeletal muscle of exhausted exercise rats. The results showed that the optimum extraction conditions of borage seed oil were as follows: liquid-material ratio 6.2∶ 1, extraction temperature 41 ℃, extraction time 53 min. Under these conditions, the extraction rate of borage seed oil was 35.32%. The content of unsaturated fatty acids in borage seed oil was 85.51%. The borage seed oil could restore the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in skeletal muscle, and reduce the content of malondialdehyde (MDA) in skeletal muscle. Borage seed oil can increase the activity of antioxidant enzymes in skeletal muscle of exhausted exercise rats, improve the body′s ability to scavenge free radicals and reduce the damage to body cells

Carbon emission trading system of China: a linked market vs. separated markets

The Chinese government intends to upgrade its current provincial carbon emission trading pilots to a nationwide scheme by 2015. This study investigates two of scenarios: separated provincial markets and a linked inter-provincial market. The carbon abatem

Ultrahigh-voltage integrated micro-supercapacitors with designable shapes and superior flexibility

With the development of power source-integrated electronics, the miniaturization of high-voltage integrated micro-supercapacitors (IMSCs) with multiple innovative form factors is urgently required but remains unsolved. Here, we demonstrate a universal, costeffective, industrially applicable protocol for fast and scalable fabrication of graphene-based planar IMSCs, with shape diversity, aesthetic versatility, outstanding flexibility and superior modularization. Using highly-conducting graphene ink, we directly screenprint shape-designable IMSCs in several seconds, consisting of hundreds to thousands of individual MSCs on arbitrary substrates. The resulting IMSCs are free of external metal current collectors and interconnects as well as separators, and exhibit exceptional electrical double-layer capacitive behaviors and remarkable flexibility. Notably, the output voltage and capacitance of IMSCs are readily adjustable through connection in well-defined arrangements of MSCs. As a proof of concept, a tandem energy storage pack of IMSCs with 130 MSCs can output a recorded voltage exceeding 100 V, demonstrative of superior modularization and performance uniformity