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A novel one-shell high temperature and high pressure semi-continuous reactor has been developed for the study of the Boudouard reaction at temperatures up to 820 °C and pressures up to 32.5 MPa. Semicontinuous gasification of charcoal using supercritical CO2 has been achieved at conversions up to 90.8% (w/w) at LSHV between 20 and 30 h−1 after 5–9 h. A gasification model is proposed and validated. Effective rates of gasification (1.32 ± 0.12) × 10−6 to (6.10 ± 2.03) × 10−5 s−1 were obtained. The results indicated that this method is technically feasible for the on-line production of high pressures streams of CO/CO2 in the lab for carrying out further chemistries, avoiding the use of CO high pressure bottles. 相似文献
33.
Marek Markowski Ireneusz Bialobrzewski Janusz Bowszys Stanislaw Suchecki 《Drying Technology》2007,25(9):1527-1536
A neural-deterministic simulation model applied for calculating distributions of temperatures and moisture content in a bed of wheat stored in a steel silo without aeration is presented in the article. The model consists of differential equations of heat and moisture transfer, initial and boundary conditions, and three artificial neural networks used during simulated ambient air conditions. Experiments and computer simulations were carried out in order to determine temperature fields in wheat grain stored in a steel silo for two months. The computer simulations were carried using MATLAB and FEMLAB software. The difference between measured and simulated temperature in grain near the silo wall at a height of 2.5 m from the bottom was less than 3.0°C. On the basis of the analysis performed it was concluded that the temperature distributions obtained with the model were consistent with the measured results obtained for grain stored in a steel silo without aeration. 相似文献
34.
10000m3/h制氧机板式换热器损坏修复后,热端跑冷严重,氧气取出量不足,制氧机工况恶化,通过分析找出了原因是因某单元氧通道堵塞,并采取了处理措施。 相似文献
35.
The durability of a cold wall MHD generator consisting of metal electrodes and alumina-coated peg insulators was experimentally examined in the oil-fired MHD condition with the additive of SO2 corresponding to S = 0.54 wt%. The structure of the electrode wall and various anode and cathode materials were tested, with particular reference to developing long-life electrodes. It was clarified that Pt, SHOMAC (28.8 Cr−1.9 Mo) and SUS-304 as anodes and W---Cu (70 W−30 Cu) and WC---Ag (60 WC−40 Ag) alloys as cathodes were promising for durability and that the structure of an anode divided into two elements connected to each other with an SnO2 resistor was very useful for uniformity of the anode corrosion pattern and the inter-anode voltages. It is reasonable to expect, from the test results, that the lifetime of a cold wall MHD generator in an oil-fired commercial plant will be over 4000 h, and therefore, a foundation for its commercial use has been established. 相似文献
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本文首先介绍国内和日本、德国、俄罗斯等国冷轧薄钢板及镀锌薄钢板的牌号、标记识别及生产地及与我国家标准薄钢板牌号的相互之间的关系,并比较具体地介绍冷轧板的实效性、镀锌薄钢板的锌层特性等诸多方面的状况。从而帮助我们在设计、制造家电产品中,比较正确地选择合适的板材。 相似文献
38.
网络存储的发展历程及新兴的iSCSI 总被引:1,自引:0,他引:1
目前SAN和NAS存储正在迅速发展,DAS的生存空间越来越小。今天超过1/3的存储是网络化的,如果不是因为FC的高成本和复杂性.这个数字还会更大。iSCSI是IETF一种新的标准协议.它将SCSI命令压缩到TCP/IP包.使数据块在IP网络上传播。和FC-SAN相比.高速千兆iSCSI耙SCSI、以太网和TCP/IP结合起来,具有许多优势.如建立在稳定和熟悉的标准上;较低的总拥有成本,安装和维修费用很低;较高程度的可操作性,减少了异构网络和电缆.使用一般的以太网交换机而不是特殊的FC交换机;等等。 相似文献
39.
Storage effects on nutritional quality of commonly consumed cereal grains are studied. Freshly harvested wheat, maize and rice grains were stored at 10, 25 and 45 °C for six months. A significant decrease in pH and an increase in titratable acidity was observed during storage of these three cereal grains at 25 and 45 °C. A gradual decline in moisture, total available lysine and thiamine contents was observed during storage. Total available lysine contents decreased by 6.50% and 18.5% in wheat, 14.3% and 20.7% in maize and 23.7% and 34.2% in rice during six months of storage at 25 and 45 °C, respectively. Six month’s storage of rice, maize and wheat grains at 25 and 45 °C resulted in reduction of thiamine contents by 16.7% and 29.2%, 17.2% and 24.1% and 21.4% and 29.5%, respectively. About 36.4–44.4% decrease in total soluble sugars at 45 °C and 9.30–31.8% increase in total soluble sugars were observed at 10 and 25 °C during six months storage of these cereal grains. Protein and starch digestibilities of cereal grains also deceased during six months of storage at 25 and 45 °C. No significant change in nutritional quality was observed during storage of cereal grains at 10 °C. 相似文献
40.