[Study on artificial compound feed for Buthus martensii].

OBJECTIVE: To solve the problem that the single feed causing malnutrition, extension of the life cycle and low survival rates of Buthus martensii. METHODS: By using Minitab (R) 15.1.1.0.0., 7 different kinds of compound feed were designed, including minced meat mud (pork,chicken and rabbit), bran (fried yellow), sugar, milk, vegetable paste and multivitamin as raw material. RESULTS: Different proportions of compound feed that taking the yellow mealworm as main component had a significant effect on the growth, mortality and birth number of Buthus martensii. Compound feed 5 significantly reduced mortality of youth scorpion. The compound feed 4 was the best in improving the weight of scorpion larvae and youth scorpion, and the farrowing number of mother scorpion. Other indicators were also good. Proportions in meatmud (pork, chicken and rabbit), bran (fried yellow), sugar, milk, vegetable paste and multivitamin was 30.00%, 25.00%, 20.08%, 15.58%, 8.08% and 1.25%, respectively. CONCLUSION: The growth of Buthus martensii is significantly influenced by the type of feed. In the production of compound feed, the yellow mealworm with compound feed 4 can be popularized.

[Study on spatial distribution pattern and seasonal distribution of Buthus martensii in yan'an].

OBJECTIVE: To study population dynamics of Buthus martensii and its wild spatial distribution pattern in Yan'an. METHODS: Every month, the 1st, 10th and 20th day were designated to collect Buthus martensii samples and count on the collection by using expansion pattern target, Taylor power law and Lwao m-x regression analysis. RESULTS: Taylor power law regression equation was Ig S2 = 1.6671 lg x + 0.1554; Lwao m-x regression equation was m = 1.3179 + 1.5133x. The spatial distribution pattern of Buthus martensii was negative binomial distribution and its population fluctuation curve in the wild presented a single peak. CONCLUSION: Spatial pattern of Buthus martensii in Yan'an is aggregated distribution which based on individual group, and the higher density,the greater aggregation degree.

Carbonyl compound emissions from passenger cars fueled with methanol/gasoline blends.

Carbonyl compound emissions from two passenger cars fueled with different methanol/gasoline blends (M15 and M100) and operated with three-way catalytic converters (TWC) were investigated. The tests were performed on a chassis dynamometer with constant volume sampling over the New European Driving Cycle (NEDC). Carbonyls were trapped on dinitrophenylhydrazine (DNPH) cartridges. The hydrazones formed on the cartridge were analyzed by means of high-performance liquid chromatography (HPLC) and detected with a variable wavelength detector. The results show that when cars were fueled with methanol/gasoline blends, carbon monoxide (CO) and total hydrocarbon (THC) emissions decreased by 9-21% and 1-55% respectively, while nitrogen oxide (NO(x)) emissions increased by 175-233%. Compared with gasoline vehicles, formaldehyde emissions with M15 and M100 were two and four times higher respectively, and total carbonyls with M15 and M100 increased by 3% and 104% respectively. With the use of the new TWC, both regulated gas pollutants and formaldehyde decreased. The new TWC caused a decrease of 5% and 31% in formaldehyde concentration for M15 and M100, respectively. Specific reactivity (SR) with the new TWC was reduced from 5.92 to 5.72 for M15 and from 7.00 to 6.93 for M100, indicating that M15 and M100 with the new TWC were friendlier to the environment.

[Investigation on emission characteristics of methanol vehicle's aldehyde and ketone pollutants].

Investigation on the character and quantity of aldehydes and ketones emitted from methanol vehicle was implemented respectively by using high performance liquid chromatograph (HPLC) method. Experiments of vehicles equipped with and without three-way catalyst (TWC) under transient and steady mode were carried out. The emission results were compared with that of gasoline vehicle. The data showed that the efficiency of aldehydes and ketones emitted from methanol vehicle and gasoline vehicle were 22.53% and 48.95% with TWC under transient state respectively. When the vehicle is fueled with methanol, the main emissions are formaldehyde, acetaldehyde, acraldehyde + acetone, and these three matters account for 97.18% of the total emission. This proportion is 39.07% when the vehicle is fueled with gasoline. However, the total quantity of aldehydes and ketones from methanol vehicle without TWC was less than that from gasoline vehicle without TWC. Whether with or without TWC, aldehydes and ketones from methanol vehicle were more than that from gasoline vehicle under steady states. When the vehicle is fueled with methanol, the emission of aldehydes and ketones is on the top level at the speed of 60 km/h, and the converting efficiency is also the highest, which is 88.50%. When at the speed of 60 km/h, 90 km/h, 120 km/h, the formaldehyde quantity of methanol vehicle was 332.94%, 374.47% and 357.58% as much as that from gasoline vehicle respectively.

[Experimental study on characteristics of biodiesel exhausted particle].

A particle emission experiment of a direct-injection turbocharged diesel engine with biodiesel and diesel was carried out. A pump of 80 L/min and fiber glass filters with diameter of 90 mm was used to sample engine particles in exhaust pipe. The size distribution, soluble organic fraction (SOF) and 16 polycyclic aromatic hydrocarbons (PAHs) of particles were analyzed by a laser diffraction particle size analyzer and GC-MS. The results indicate that the volume weighted size distribution of biodiesel particle is single-peak and its median diameter d(0.5) and mean diameter d32 are decreased with the increasing speed. At the high speed the d32 and d(0.5) of biodiesel are larger than those of diesel, and quite the contrary at the low speed. SOF mass concentration and mass percentage of biodiesel are 12.3 - 31.5 mg/m3 and 38.2% - 58.0% respectively, which are much higher than those of diesel. The total PAHs emission concentration of biodiesel is 2.9 - 4.7 microg/m3 lower than that of diesel as much as 29.1% - 92.4%.

[Experimental study on particle size distributions of an engine fueled with blends of biodiesel].

The purpose of this study is to obtain the particle size distributions of an engine fueled biodiesel and its blends. A turbocharged DI diesel engine was tested on a dynamometer. A pump of 80 L/min and fiber glass filters with diameter of 90 mm were used to sample engine particles in exhaust pipe. Sampling duration was 10 minutes. Particle size distributions were measured by a laser diffraction particle size analyzer. Results indicated that higher engine speed resulted in smaller particle sizes and narrower distributions. The modes on distribution curves and mode variation were larger with dry samples than with wet samples (dry: around 10 - 12 microm vs. wet: around 4 - 10 microm). At low speed, Sauter mean diameter d32 of dry samples was the biggest with B100, the smallest with diesel fuel, and among them with B20, while at high speed, d32 the biggest with B20, the smallest with B100, and in middle with diesel. Median diameter d(0.5) also reflected the results. Except for 2 000 r/min, d32 of wet with B20 is the biggest, the smallest with diesel, and in middle with B100. The large mode variation resulted in increase of d32.

[Preparation of biodiesel from waste edible oils and performance and exhaust emissions of engines fueled with blends of the biodiesel].

The purpose of this study is to evaluate the effect of biodiesel on environment and to investigate the effect of the biodiesel made of waste edible oils on the performance and emissions of engines. Life cycle assessment (LCA) of biodiesel and diesel was introduced and the results of the LCA of both the fuels were given. The technological process of biodiesel production from waste edible oils, which is called transesterification of waste oils and methanol catalyzed with NaOH, was presented. Two turbocharged DI engines fueled with different proportions of biodiesel and diesel, namely, B50 (50% biodiesel + 50% diesel) and B20 (20% biodiesel + 80% diesel), were chosen to conduct performance and emission tests on a dynamometer. The results of the study indicate that there was a slight increase in fuel consumption by 8% and a drop in power by 3% with the blends of biodiesel, compared with diesel, and that the best improvements in emissions of smoke, HC, CO and PM were 65%, 11%, 33% and 13% respectively, but NOx emission was increased. The study also shows that it is satisfied to fuel engines with the low proportion blends of the biodiesel, without modifying engines, in performance and emissions.