基于遥感生态指数模型的杨凌农业高新技术产业示范区生态环境评价

[目的]定量揭示杨凌农业高新技术产业示范区(简称"杨凌区")生态环境质量的空间分布与变化特征,为该区及类似地区生态环境建设的规划和管理提供科学依据。[方法]本文基于Landsat8卫星影像,利用主成分分析的遥感生态模型进行分析。[结果]2013—2018年,杨凌区生态环境质量总体呈上升趋势,遥感生态指数均值由0.45升至0.50,呈上升趋势的面积为50.77km^2,占全区总面积的38%;杨凌区生态环境状况的空间分布具有向西北优而东南城区差两极扩散的趋势;干度分量对生态指数模型整体影响最大。[结论]杨凌区生态环境质量较差的区域主要集中在城区人为活动密集区和大型工业园区,体现出高度聚集的特点。在杨凌区未来规划和发展中,应控制并有效减小裸地和建设用地面积,重视生态景观和城区绿化。

Novel Distributed Fiber Bragg Grating Sensing System Based on M-Z Interferometer

One of the problems in using grating sensors is how to measure a small Bragg wavelength shift accurately. Nowadays demodulation techniques are mainly based on the edge filter, tunable filter, or interferometric scanning methods. Interferometric demodulation is widely accepted as the technology which can provide the high sensitivity. An interrogation system using the interferometric scanning method is presented, in which an unbalanced fiber M-Z interferometer is used as the wavelength scanner for temperature measurement. A novel fiber Bragg grating sensor system based on M-Z interferometric demodulation technique is presented in this paper. The temperature sensitivity measured in the experiment is almost consistent with that obtained from the theoretic calculation.

Novel technology on preparation of double-layered pellets for sulfur and arsenic-bearing gold concentrates

Double-layered pellet （DLP） roasting is a novel pretreatment method for sulfur and arsenic-bearing gold concentrates. In this process, preparation of DLPs is a fundamental step which is required to produce DLPs with favorable mechanical strength and thermal stability. Studies were carried out to investigate the affecting factors and conditions on the preparation and properties of DLPs. The results show that moisture content has significant influence on DLPs preparation. With the increase of moisture content in the range of no more than 9.8%, drop resistance and compressive strength of green DLPs are raised and the pelletizing dynamics is improved accordingly. The optimum conditions are determined as moisture content of 9.8%, coating time of 14-16 min, drying temperature 〈80 ℃and drying gas velocity 〈1.2 m/s. When DLPs prepared under these conditions are roasted at 600 ℃ for 1 h, favorable removal and solidifying rates can be obtained, in which the removal rates of arsenic and sulfur are 94.38% and 82.55%, and the solidifying rates of arsenic and sulfur reach 99.62% and 99.79%, respectively. These results promise industrial application of DLP roasting.

Sweet Corn Production and Nutritive Value of Stover with Manure Enriched with Rock Phosphate Fertilizer and Biodecomposer

Zea mays var. saccharata （sweet corn） is an important crops grown for food and feed in the tropics. In Indonesia, most of the land used for crops production is characterized by acid pH and low levels of nitrogen and phosphorus. Phosphorus fertilizers have been widely used to improve soil fertility in Indonesia. Given the high cost of superphosphate （SP）, the focus is now on rock phosphate （RP） fertilizer, which is relatively cheaper than SP and shows high solubility in acid condition. The combination of RP and manure during the decomposing process and the addition of decomposing microbes may be a promising technique to overcome the problem. A field experiment was conducted on a vertisol soil （low pH and low available nitrogen and phosphorus）. The objective of the research is to evaluate the effect of combinations of manure enriched with RP （granular and non-granular） with three different decomposing microbes （EM4, starTmik and stardec） on sweet corn and dry matter production, phosphorus （P） and calcium （Ca） content in above-ground biomass. A completely randomized design with seven treatments and four replicates was used in this experiment. The size of the plots was 3 m x 2.5 m. The treatments were TO （manure）, T1 （manure ＋ EM4）, T2 （manure ＋ starTmik）, T3 （manure ＋ stardec）, T4 （manure granular ~ EM4）, T5 （manure granular ＋ starTmik）, T6 （manure granular ＋ stardec）. The manure was enriched with RP 66 kg P/ha （150 kg P2Os/ha） and inoculated with the biodecomposer according to the assigned treatment. The manure was applied in a rate of 30 t/ha. All plot received 125 kg KC1/ha （150 kg K20/ha） and 200 kg urea/ha as basal fertilization. Sweet corn was harvested 70 d after planting. Sweet corn plants were cut close to the ground and analyzed for dry matter yield （DM） and P and Ca content in the biomass. Result showed that sweet corn and DM yield and P content were not significantly influenced by the treatments. Ca content in the above-ground biomass, in turn, differed among the treatments. Manure enriched with RP fertilizer was not significantly diferent on Ca content of stover. Thus, it seems that no gain occurs in sweet corn production and nutritive value of stover from the addition of microbes to manure enriched with RP in a acid vertisol soil. In conclusion, manure enriched with RP with or without biodecomposer, in granular or non-granular form, resulted in similar on sweet corn and DM production, P and Ca content of stover.

Characterization of Atomization Processes in Suspension/Emulsion Sprays

The characterization of suspension/emulsion sprays plays a decisive role in many industrial processes. A good example of such a process is the drying of a milk spray to produce milk powder, where the process efficiency and product quality is typically controlled by atomization parameters like flow rate, pressure, etc.. However, these parameters influence directly the droplet size and droplet velocity distributions in a spray, so that optimizing a spray drying process often involves adjusting the spray to a desired droplet size and droplet velocity distribution. This requires a measurement technique capable of characterizing in real time, the droplets in a suspension/emulsion spray. To achieve this aim, we present developments to the well-known time-shift technique for spray measurements.

A novel three-component hybrid-integrated optical accelerometer based on a Mach-Zehnder interferometer with a LiNbO_3 photoelastic waveguide

An investigation of the properties ofa LiNbO3 photoelastic waveguide via the acceleration-induced effect is presented. A novel three-component hybrid-integrated optical accelerometer based on a Mach-Zehnder interferometer with a LiNbO3 photoelastic waveguide has been designed, which is capable of detecting seismic acceleration in high-accuracy seismic exploration. The Mach-Zehnder interferometer was successfully fabricated and a lighting test used to check its quality. The frequency response characteristic of the accelerometer was measured2 The accelerometer with a resonant frequency of 3549 Hz was demonstrated to show good linear frequency responding characteristics in the range of 100-3000 Hz. The accelerometer also shows good stability and consistency. Experimental results indicate that the outputs of the on- and cross-axis are 147 and 21.3 mV, respectively.