Viscosity estimation for slags containing calcium fluoride

Based on recently published experimental data, the Riboud model was modified for viscosity estimation of the slags containing calcium fluoride. The estimated values were in good agreement with measured data. Reasonable estimation can be achieved using the modified Riboud model for mould fluxes and ESR (eletro slag remelting) slags. Especially for ESR slags, the modified Riboud model can provide much more precise values than the original Riboud model.     

基于ARM11的机房环境监控报警系统的设计与实现

为了确保计算机机房环境条件的稳定,并使机房监控无人值守,达到高效的管理和安全运营,提出了基于ARM11的环境监控报警系统;硬件设计主要有数据采集模块、带有触摸屏的ARM11系统板和GSM模块;其工作原理:数据采集模块采集机房环境信息,将采集到的数据利用Modbus协议传给ARM控制器,控制器处理信息后通过AT指令控制GSM模块通信,实现手机短信报警机制,简单方便有效,具有很强的实用性;测试结果表明:该系统不仅做到遥测、遥控,还可以在ARM终端查看、存储历史数据。     

Hybrid simulation and optimization-based design and operation of integrated photovoltaic generation,storage units,and grid

Unlike fossil-fueled generation, solar energy resources are geographically distributed and highly intermittent, which makes their direct control extremely difficult and requires storage units as an additional concern. The goal of this research is to design and develop a flexible tool, which will allow us to obtain (1) an optimal capacity of an integrated photovoltaic (PV) system and storage units and (2) an optimal operational decision policy considering the current and future market prices of the electricity. The proposed tool is based on hybrid (system dynamics model and agent-based model) simulation and meta-heuristic optimization. In particular, this tool has been developed for three different scenarios (involving different geographical scales), where PV-based solar generators, storage units (compressed-air-energy-storage (CAES) and super-capacitors), and grid are used in an integrated manner to supply energy demands. Required data has been gathered from various sources, including NASA and TEP (utility company), US Energy Information Administration, National Renewable Energy Laboratory, commercial PV panel manufacturers, and publicly available reports. The constructed tool has been demonstrated to (1) test impacts of several factors (e.g. demand growth, efficiencies in PV panel and CAES system) on the total cost of the integrated generation and storage system and an optimal mixture of PV generation and storage capacity, and to (2) demonstrate an optimal operational policy.     

Investigation on the thermal decomposition of aged La2O3

The thermal decomposition process of air-aged La203 in argon atmosphere was studied using nonisothermal TG-DSC. X-ray diffraction and TG-DSC analysis showed that the aged powder was composed of La（OH）3 with small amounts of oxycarbonate. The decomposition process of air-aged La2O3 involves the two-step decomposition of La（OH）3 and the decomposition of oxycarbonate. The kinetic analysis of the two-step decomposition of La（OH）3 was carried out using Coats-Redfern and isoconversion （Ozawa） methods. The kinetics of the two-step decomposition can be described in terms of the nucleation and growth model A （m=1.5, m is the model parameter） and A （m=2.5）, respectively. The apparent activation energy for the first step is 136-144 （Coats-Redfern） and 137-164 kJ/mol （isoconversion）. The apparent activation energy for the second step is 191-194 （Coats-Redfern） and 186-213 kJ/mol （isoconversion）.     

Experimental study on upward bubble velocity and pierce length distributions in a water model of copper converter

The upward bubble velocity and the pierce length distributions in a sectional water model of the copper converter in Guixi Smelter in Jiangxi, China, were measured using a two-contact electro-resistivity probe. In the case of using a single tuyere, the bubble velocity distribution along longitudinal direction was similar to that derived from Guassian function. Beyond the center of the longitudinal range, the bubble pierce length exhibited a sudden increase. The upward bubble velocity at a specified location could go up to meters per second. Its probability at a fixed location obeys a lognormal function; the bubble pierce length there varies bellow a few centimeters. In the case of using multi-tuyeres, the upward bubble velocity was roughly uniform right above the tuyeres and showed a slow decrease beyond this region. The bubble pierce length within both of these two regions was roughly uniform. Its average value in the former region, however, was found to be somewhat lower than that in the later.     

Observer-based backstepping dynamic surface control for stochastic nonlinear strict-feedback systems

An observer-based dynamic surface control approach is proposed for a class of stochastic nonlinear strict-feedback systems in order to solve the problem of ‘explosion of complexity’ in the backstepping design; that is, the dynamic surface control approach is extended to the stochastic setting. The circle criterion is applied to designing a nonlinear observer, and so no linear growth condition is imposed on nonlinear functions depending on system states. It is proved that the closed-loop system is semi-globally uniformly ultimately bounded in fourth moment, and the ultimate boundedness can be tuned arbitrarily small. Two examples are given to demonstrate the effectiveness of the control scheme proposed in this paper.     

Effects of Atmospheric Pressure Air Plasma Pretreatment on the Seed Germination and Early Growth of Andrographis paniculata

The objective of this paper is to demonstrate whether air plasma can change the seed germination characteristics, seedling emergence, as well as biochemical reactivity, in Andrographis paniculata （A. paniculata） seedlings by modifying the seed coat and finding a beneficial treatment dose. Eight treatment doses and one control were used to conduct electrical conductivity determination, a germination test, a seedling emergence test and a biochemical assay. The results showed that after being treated with air plasma excited at 5950 V for 10 s, the perme- ability of the seeds was improved significantly, resulting in the acceleration of seed germination and seedling emergence. In the meantime, the catalase activity and catalase isoenzyme expression were also improved, while the malondialdehyde content in the seedlings was decreased （which means greater counteraction with environmental stress）. After being treated with 4250 V for 10 s and 5950 V for 20 s, the seed germination was enhanced, but without an obvious change in seedUng emergence. However, after treatment with 3400 V for 20 s and 5100 V for 10 s, the permeability of the seeds was decreased, resulting in a delay in seedling emergence. These results indicate that air plasma can change the physiological and biochemical characteristics of Andrographis paniculata seeds by modifying the seed coat, combined with the effects of the active plasma species, and that different treating doses have different effects.     

2018年以来全球矿业市场态势分析

2018年以来,全球主要经济体贸易摩擦升级,世界经济复苏乏力。矿产品价格整体呈下降态势,黄金、铁矿石、镍等矿产品价格因贸易战、地缘政治等多种因素影响短期内快速上涨。主要矿业公司股价震荡回升。全球固体矿产勘查投入持续上涨,中国固体矿产勘查投入仍然走低。全球勘查投入来看,大型公司成为投入主体。后期勘探投入占比持续增长；勘查投入主要聚焦在金、铜、锌等矿种。大型矿业公司大幅降低非洲、东南亚等地区勘查投入。全球矿业发展呈现新的分化态势。     

离子凝胶复合吸附剂的制备及空气取水性能

制备了一种LiCl复合可得然离子凝胶,并将其首次用于空气取水性能研究。在不同吸附温度、吸附湿度的开式环境中,完成了复合吸附剂的水蒸气吸附特性研究。探究了浸渍盐的质量浓度对复合吸附剂吸附性能的影响。根据目标工况,完成了复合吸附剂组分的优化配比。对优化后的离子凝胶进行了吸附动力学和等温吸附特性研究。结果表明,15% LiCl溶液复合而成的可得然吸附剂综合性能最佳。在35℃&75%RH下,该复合吸附剂的吸附量高达3.30g/g,是传统硅胶复合吸附剂的6.6倍;在55℃&40%RH工况下实现1.66 g/g的水量脱附,是硅胶复合吸附剂的3倍。在25℃&75%RH下,可得然复合凝胶吸附剂的吸附速率K高达3.48×10^-3s^-1;该离子凝胶复合吸附剂的研究,为吸附式空气取水技术提供了基础支持。     

联合调理技术在生化污泥调理中的应用

本文对联合调理技术在生化污泥调理中的应用进行了综述。主要介绍了药剂联合调理、化学调理和物理调理联用技术以及污泥联合调理技术,并展望了联用调理技术在污泥调理中的发展方向。