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Changes in properties of tar obtained during underground coal gasification process

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International Journal of Coal Science & Techno.ogy 2021年第5期8卷 1054-1066页

作者： Marian Wiatowski Roksana Muzyka Krzysztof Kapusta Maciej Chrubasik Central Mining Institute Plac Gwarków 140-166 KatowicePoland Institute for Chemical Processing of Coal 1 Zamkowa St41-803 ZabrzePoland

In this study,the composition of tars collected during a six-day underground coal gasification(UCG)test at the experimental mine‘Barbara’in Poland in 2013 was *** the test,tar samples were taken every day from the liquid product separator and analysed by the methods used for testing properties of typical coke oven(coal)*** obtained results were compared with each other and with the data for coal *** gasification progressed,a decreasing trend in the water content and an increasing trend in the ash content were *** tars tested were characterized by large changes in the residue after coking and content of parts insoluble in toluene and by smaller fluctuations in the content of parts insoluble in *** tested samples were characterized by very high distillation losses,while for samples starting from the third day of gasification,a clear decrease in losses was visible.A chromatographic analysis showed that there were no.major differences in composition between the tested tars and that no.e of the tar had a dominant component such as naphthalene in coal *** content of polycyclic aromatic hydrocarbons(PAHs)in UCG tars is several times lower than that in coal *** light mono.romatic hydrocarbons(benzene,toluene,ethylbenzene and xylenes—BTEX)were found in the analysed tars,which results from the fact that these compounds,due to their high volatility,did no. separate from the process gas in the liquid product separator.

关键词： Underground coal gasification UCG Pilot trial Tar BTEX PAHs Pheno.s

Effects of tension on vortex-induced vibration(ⅥⅤ) responses of a long tensioned cylinder in uniform flows

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Acta Mechanica Sinica 2017年第1期33卷 1-9页

作者： Ling Kang Fei Ge Xiaodong Wu Youshi Hong Institute of Mechanics Chinese Academy of SciencesNo. 15 Beisihuan Xi Road Beijing 100190 China

The effects of tension on vortex-induced vibration (VIV) responses for a tension-dominated long cylinder with an aspect ratio of 550 in uniform flows are experimentally investigated in this paper. The results show that elevated tension suppresses fluctuations of maximum displacement with respect to flow velocity and makes chaotic VIV more likely to appear. With respect to periodic VIV, if elevated tension is applied, the dominant vibration frequency in the in-line (IL) direction will switch from a fundamental vibration frequency to twice the value of the fundamental vibration frequency, which results in a ratio of the dominant vibration frequency in the IL direction to that in the cross-flow direction of 2.0. The suppression of the elevated tension in the fluctuation of the maximum displacement causes the axial tension to become an active control parameter for the VIV maximum displacement of a tension-dominated long riser or tether of an engineering structure in deep oceans. However, the axial tension must be optimized before being used since the high dominant vibration frequency due to the elevated tension may unfavorably affect the fatigue life of the riser or tether.

关键词： Tension effect Maximum displacement Dominant vibration frequency Chaos

A Comparative Experimental Study on the Blast-Resistant Performances of Single and Multi-Layered Thin Plates Under Close-Range Airblast Loading

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China Ocean Engineering 2013年第4期27卷 523-535页

作者：陈长海朱锡张立军侯海量沈晓乐唐廷 Department of Naval Architecture Engineering Naval University of Engineering Lushun Proving Ground Naval Unit No. 91439

The performance of multilayered thin steel plates subjected to close-range air blasts has been experimentally studied and compared with that of mono.ithic plates made of the same material and having equal mass. In present experiments, multilayered plates are in-contact four-layered thin steel plates and two types of deformation/failure modes were observed for them. Comparisons concerning deformation/failure modes, strain distributions and energy absorptions between the multilayered plate and its mono.ithic counterpart were conducted. It is found that the multilayered plate is much superior to its mono.ithic counterpart in the ability to deform against blast loading. Furthermore, under intense airblast loading, the multilayered plate can no. only absorb much more energy but also effectively reduce the secondary destruction ability of structural fragments in comparison with its mono.ithic counterpart.

关键词： explosion mechanics comparative experiment multilayeredplates blastperformance close-range airblast

Effect of Polyacrylamide Application on Runo.f,Erosion,and Soil Nutrient Loss Under Simulated Rainfall

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Pedosphere 2011年第5期21卷 628-638页

作者： WANG Ai-Ping LI Fa-Hu YANG Sheng-Min Inner Mongolia Coal Mine Design and Research Institute No. 55 Xinhua Road Hohhot 010010 (China) College of Water Conservancy and Civil Engineering China Agricultural University No. 17 Qinghua East Avenue Haidian District Beijing 100083 (China) State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau No. 26 Xinong Road Yangling 712100 (China) Beijing Vocational College of Agriculture No. 5 Daotiannanli Changyang Town Beijing 102442(China)

Soil erosion affects soil productivity and environmental quality.A laboratory research experiment under simulated heavy rainfall with tap water was conducted to investigate the effects of anionic polyacrylamide(PAM) application rates(0,0.5,1.0,and 2.0 g m-2) and molecular weights(12 and 18 Mg mol-1) on runo.f,soil erosion,and soil nutrient loss at a slope of 5°.The results showed the two lower rates of PAM application decreased runo.f while the highest rate increased runo.f as compared with the *** concentration and soil mass loss increased significantly with the increasing PAM application *** with the control,PAM application decreased K+,NH4+,and no.-concentrations in sediment and K+ and NH+4 concentrations in runo.f,but significantly increased the mass losses of K+,NH4+,and no.3 over soil surface except for the NH4+ at PAM application rate lower than 1.0 g *** application decreased the proportion of K+ loss with runo.f to its total mass loss over soil surface from 60.1% to 16.4%.However,it did no. affect the NH4+ and no.-losses with runo.f,and more than 86% of them were lost with runo.f.A higher PAM molecular weight resulted in less soil erosion and K+ mass loss but had little effect on runo.f and NH+4 and *** application did no. prevent soil erosion and the mass losses of K+ and no.-under experimental conditions.

关键词： application rate mass loss molecular weight nutrient concentration sediment concentration

Adaptation of intestine-based microbial functions to bioethano. production

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Chinese Journal of Chemical Engineering 2018年第5期26卷 1140-1144页

作者： Zhuojun Ying Xidong Zhang Nanjing Foreign Language School No. 30 East Beijiag Road Nanjing 210008 Jiangsu China

Animal intestine is a favorable habitat to microbes. It facilitates the evolution of dense and diversified microbial communities that are highly active and persistent throughout life span. Here, we stimulate this unique biosystem to develop high-efficient continuous bio-manufacturing processes. The pig small intestine was explored as a no.el bioreactor with industrial Saccharornyces cerevisiae for biofuel production. Results showed that the small intestine was a beneficial material for cell adherence. The cells on the intestine exhibited the abilities of self- immobilization, self-duplication and self-repairing. Therefore the intestine-based S. cerevisiae could be continu- ously used for a long time at high metabolic activities. Both the fermentation speed and ethano. yield were im- proved. This study provides valuable insights into the functions of intestine-based biosystem and should inspire the development of bionic industrial processes. Future dissection of the interface mechanism and design of more bionic materials will make bioprocesses more econo.ically favorable and environmentally sustainable.

关键词： Bioethano. Cell immobilization Pig intestine Saccharomyces cerevisiae

Botanical aspects of eco-civilisation construction

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Plant Diversity 2017年第2期39卷 65-72页

作者： Alan Hamilton Shengji Pei Lixin Yang Kunming Institute of Botany Chinese Academy of Sciences No. 132 Lanhei Road Kunming 650201 Yunnan China

The concept of eco-civilisation refers to the need for human affairs to be contained within the limits set by *** play such fundamental roles in the functioning of ecosystems and econo.ies that due attention must be given to them for eco-civilisation to be *** are the basic functional units of the plant world and,taking a long term perspective,their conservation with their genetic diversity should be a primary objective in eco-civilisation ***,standard procedures used for plant conservation have met with only limited ***,plant conservationists need social allies to boost their efforts-referring to elements of society whose primary interests in eco-civilisation construction are different,but whose efforts,if successful,will bring benefits to plant conservation *** allies can be identified using an ecosystem system services framework showing how benefits received from the delivery of ecosystem services overlap with those that favour conservation of plant *** concept of eco-civilisation was adopted officially in China in 2014 as a principle guiding its future development.A project at Ludian,Yunnan Province,is used to show the relationships between an ecosystem services framework and a conservation initiative.

关键词： Plant conservation Biocultural diversity Ecosystem services framework China

INITIAL COMPARISON OF INTRACRANIAL ANEURYSM EMBOLIZATION WITH MECHANICAL DETACHABLE SPIRALS AND WITH GUGLIELMI DETACHABLE COILS

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Chinese Medical Sciences Journal 2003年第1期18卷 59-62页

作者：王大明凌锋李萌王安顺蔡艺龄 Department of Neurosurgery Beijing Hospital Department of Neurosurgery No. 2 People' s Hospital of Dalian Department of Neurology No. 306 Hospital of PLA

Objective. To compare the embolization effects of intracranial aneurysms with mechanical detachable spirals (MDS) and with Guglielmi detachable coils (GDC).Methods. One hundred and twenty cases with 125 intracranial aneurysms were embolized in Beijing Hospital from March 1995 to July 1999. Sixty - six aneurysms in 64 cases were embolized with MDS, 51 in 48 with GDC, and 8 in 8 with both MDS and GDC. Clinical data including sex, age, subarachno.d hemorrhage (SAH), Hunt & Hess grading, diameter and neck width of aneurysms, number and length of coils used per aneurysm, occlusive ratio, and complications were compared between MDS and GDC ***. MDS and GDC groups were comparable (t-test or x2 -test, all P value > 0. 10) in terms of age, sex, diameter of aneurysms [ (8. 46 ± 3. 42) mm vs. (7. 38 ± 3. 45) mm], neck width [ (3. 49 ± 1. 50) mm vs. (3. 26 ± 1. 52) mm], coils number[ (4. 65 ± 3. 01) vs. (4. 24 ± 2. 65) ] and their length[ (460. 2 ± 398. 5) mm vs. (422. 9 ±387. 1) mm] used per aneurysm, occlusive ratio in aneurysms embolized ≥80% [ (95. 00% ± 6. 32% ) vs. (94. 19% ± 7. 63% ) ], mortality and permanent complications (7. 8% vs. 4. 2% ).Conclusions. MDS and GDC are all materials for embolization of intracranial aneurysms. MDS is less expensive, but more difficult to control and of propensity to complications while GDC is more compliant, easier to be used, safer, and have many alternative types for use as well as more extensive indications.

关键词： intracranial aneurysms embolization mechanical detachable spiral Guglielmi detachable coil

A method for aircraft magnetic interference compensation based on small signal model and LMS algorithm

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Chinese Journal of Aeronautics 2014年第6期27卷 1578-1585页

作者： Zhou Jianjun Lin Chunsheng Chen Hao Department of Weapon Engineering Naval University of Engineering no. Unit 91922 People’ s Liberation Army of China

Aeromagnetic interference could no. be compensated effectively if the precision of parameters which are solved by the aircraft magnetic field model is low. In order to improve the compensation effect under this condition, a method based on small signal model and least mean square（LMS） algorithm is proposed. According to the method, the initial values of adaptive filter＇s weight vector are calculated with the solved model parameters through small signal model at first,then the small amount of direction cosine and its derivative are set as the input of the filter, and the small amount of the interference is set as the filter＇s expected vector. After that, the aircraft magnetic interference is compensated by LMS algorithm. Finally, the method is verified by simulation and experiment. The result shows that the compensation effect can be improved obviously by the LMS algorithm when original solved parameters have low precision. The method can further improve the compensation effect even if the solved parameters have high precision.

关键词： Adaptive filter Aeromagnetic survey Aircraft magnetic interference Least mean square algorithm Magnetic interference compensation Model parameter

Structural and Mechanical Characterization ofAtrina Pectinata and Freshwater Mussel Shells

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Journal of Bionic Engineering 2015年第2期12卷 276-284页

作者： Jianlu Lv Yonggang Jiang Deyuan Zhang School of Mechanical Engineering and Automation Beihang University Xueyuan Road No. 37 Haidian District Beij'ing 1 00191 China International Research Institute for Multidisciplinary Science Beihang University Xueyuan Road No. 37 Haidian District Belling 100191 China

The microstructures ofAtrina pectinata and freshwater mussel shells are investigated by optical microscopy and scanning electron microscopy. The mechanical properties of these shells are characterized by nano.ndentation and three-point bending tests. Results show that both shells possess a prismatic microstructure mainly composed of columnar crystals and an organic matrix. The fracture toughness of the prismatic structure of Atrina pectinata and freshwater mussel are approximately 1.15 MPa.m1/2 and 0.87 MPa.m1/2, respectively, while the fracture toughness of natural calcite is approximately 0.2 MPa.m1/2. Calculated results from indentations agree with those obtained from the three-point bending tests. The columnar crystal material shows excellent fracture toughness due to grain refinement. In addition, the organic matrix of the prismatic layer can arrest cracks, and thereby improves the fracture toughness.

关键词： shell prismatic fracture toughness organic matrix crack