检索结果-南通市图书馆

Role of iron ore in enhancing gasification of iron coke:Structural evolution,influence mechanism and kinetic analysis

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 58-69页

作者： Jie Wang Wei Wang Xuheng Chen Junfang bao Qiuyue Hao heng zheng Runsheng Xu School of Chemistry and Materials Science Hubei Engineering UniversityXiaogan 432000China Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081China Institue of Ironmaking Technology Baosteel Central Research InstituteShanghai 201999China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

The utilization of iron coke provides a green pathway for low-carbon *** uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the microstructure of iron coke was ***,a comparative study of the gasification reactions between iron coke and coke was conducted through non-isothermal thermogravimetric *** findings indicate that compared to coke,iron coke exhibits an augmentation in micropores and specific surface area,and the micropores further extend and *** provides more adsorption sites for CO_(2) molecules during the gasification process,resulting in a reduction in the initial gasification temperature of iron *** the heating rate in non-isothermal gasification can enhance the reactivity of iron *** metallic iron reduced from iron ore is embedded in the carbon matrix,reducing the orderliness of the carbon structure,which is primarily responsible for the heightened reactivity of the carbon *** kinetic study indicates that the random pore model can effectively represent the gasification process of iron coke due to its rich pore ***,as the proportion of iron ore increases,the activation energy for the carbon gasification gradually decreases,from 246.2 kJ/mol for coke to 192.5 kJ/mol for iron coke 15wt%.

关键词： low-carbon ironmaking iron coke gasification structural evolution kinetic model

在线全文

学校读者我要写书评

暂无评论

小檗碱衍生物的红外、紫外及核磁共振光谱

华西药学杂志 1987年第2期 90-94页

作者：郑保忠何菱胥佩菱华西医科大学药学院华西医科大学药学院成都

本文通过对九个合成小檗碱衍生物的红外、紫外和核磁共振氢谱的解析,确证了其化学结构,其中有六个化合物尚未见诸文献报导。

关键词：小檗碱假小檗碱红外光谱紫外光谱核磁共振氢谱

Desulfurization kinetics of ZnO sorbent loaded on semi-coke support for hot coal gas

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2012年第5期21卷 556-562页

作者： Zhiwei Ma Xianrong zheng Liping Chang Ruiyuan he Weiren bao Key Laboratory of Coal Science and Technology Taiyuan University of TechnologyMinistry of Education and Shanxi ProvinceTaiyuan 030024ShanxiChina

Zn-based sorbent （Z20SC） prepared through semi-coke support in 20 wt% zinc nitrate solution by high-pressure impregnation presents an excellent desulfurization capacity in hot coal gas,in which H2 S can not be nearly detected in the outlet gas before 20 h breakthrough *** effects of the main operational conditions and the particle size of Z20SC sorbent on its desulfurization performances sorbent were investigated in a fixed-bed reactor and the desulfurization kinetics of Z20SC sorbent removing H2 S from hot coal gas was calculated based on experimental *** showed that the conversion of Z20SC sorbent desulfurization reaction increased with the decrease of the particle size of the sorbent and the increases of gas volumetric flow rate,reaction temperature and H 2 S content in inlet gas.Z20SC sorbent obtained from hydrothermal synthesis by high-pressure impregnation possessed much larger surface area and pore volume than semi-coke support,and they were significantly reduced after the desulfurization *** equivalent grain model was reasonably used to analyze experimental data,in which k s=4.382×10-3 exp（-8.270×103/RgT） and Dep=1.262×10-4exp（1.522×104/RgT）.It suggests that the desulfurization reaction of the Z20SC sorbent is mainly controlled by the chemical reaction in the initial stage and later by the diffusion through the reacted sorbent layer.

关键词： desulfurization kinetics Zn-based sorbent hot coal gas medium-temperature desulfurization

Synthesis, Dimeric Crystal Structure, and Biological Activities of N-(4-Methyl-6-oxo-1,6-dihydro-pyrimidin-2-yl)-N′-(2-trifluoromethyl-phenyl)-guanidine

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2006年第6期22卷 768-771页

作者： he Feng-qi WANG bao-lei LI zheng-ming Elemento-Organic Chemistry Institute State-Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 P. R. China

The title compound, N-（4-methyl-6-oxo-1,6-dihydro-pyrimidin-2-yl）-N＇-（2-tritluoromethyl-phenyl）-guanidine, was synthesized and its structure was confirmed by using IR, MS,^1H NMR, and elemental analysis. The single crystal structure of the title compound was determined by X-ray diffraction. The preliminary biological test showed that the synthesized compound has a weak herbicidal activity.

关键词： Ketol-acid reductoisomerase Synthesis X-ray diffraction Crystal structure Biological activity

Synthesis and Crystal Structure of 1-[4-(Pyrimidin-2-yl)piperazin-1-ylmethyl]-1H-benzotriazole

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2006年第5期25卷 543-546页

作者： he Feng-Qi WANG bao-Lei LI zheng-Ming SONG Hai-Bin Elemento-organic Chemistry Institute State Key Laboratory of Elemento-organic Chemistry Nankai University Tianjin 300071 China

The crystal structure of the title compound （C15H17N7, Mr = 295.36） has been determined by single-crystal X-ray diffraction. The crystal belongs to triclinic, space group P1^- with a = 6.370（2）, b = 9.830（3）, c = 11.821（4） A, α = 89.603（6）, β = 86.018（6）, γ = 85.850（6）°, V = 736.5（4） A^3, Z= 2, F（000） = 312, Dc = 1.332 g/cm^3, μ = 0.087 mm^-1, the final R = 0.0476 and wR = 0.1079 for 1494 observed reflections with Ⅰ 〉 2σ（Ⅰ）. X-ray analysis reveals that the piperazine ring of the title compound is in a chair conformation. In addition, in the crystal structure there also exist intramolecular C-H…N hydrogen bonds and intermolecular π-π interactions between benzotriazole rings.

关键词： X-ray diffraction crystal structure synthesis

Characterization and numerical simulation of nucleation-growth-coarsening kinetics of precipitates in G115 martensitic heat resistance steel during long-term aging

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2023年第6期30卷 1279-1290页

作者： Yun-he Yu zheng-dong Liu Zhen Liu zheng-zong Chen Han-sheng bao Chi Zhang Zhi-gang Yang Shagang School of Iron and Steel Soochow UniversitySuzhou 215137JiangsuChina Key Laboratory for Advanced Materials of Ministry of Education School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Research Institute of Special Steels Central Iron and Steel Research InstituteBeijing 100081China

The service performance of heat resistance steels is largely determined by the precipitation *** nucleation-growth-coarsening behaviors of precipitates in G115 martensitic heat resistance steel during long-term aging at 650℃ have been systemically *** microstructural characteristics,precipitate morphology and alloying element distribution were studied by scanning electron microscopy,transmission electron microscopy and scanning transmission electron *** lognormal distribution fitting combined with the multiple regression analysis was adopted to evaluate the precipitate size *** phase has longer incubation time,and its coarsening rate is almost one order of magnitude higher in comparison with that of M_(23)C_(6) ***,the nucleation rate,number density,average radius,and volume fraction of two precipitates are simulated based on the classical nucleation theory and the modified Langer-Schwartz *** precipitation behavior of Laves phase can be well explained with the Fe-W system as the interfacial energy takes 0.10 J/m^(2).In contrast,the simulation results of M_(23)C_(6) carbide in the Fe-Cr-C system are significantly overestimated,which results from the inhibitory effect of boron on coarsening.

关键词： Nucleation Growth Coarsening Precipitation kinetics G115 heat resistance steel Long-term aging

(2-羟基-3-壬苯基)丙基三乙基氯化铵的合成及性能的研究

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

齐齐哈尔大学学报（自然科学版） 2001年第1期17卷 15-18页

作者：贾丽华郭祥峰张德庆陆铭齐齐哈尔大学齐齐哈尔161006

以壬基酚、环氧氯丙烷和三乙胺为原料一步合成了（2-羟基-3-壬苯基）丙基三乙基氯化铵新型阳离子表面活性剂。对其表面张力，cmc，泡沫性能，絮凝能力等进行了测定。

关键词：壬基酚季铵盐表面活性剂合成性能

Failure analysis of ring die of a feed pellet machine

在线全文

学校读者我要写书评

暂无评论

China Foundry 2020年第2期17卷 167-172页

作者： he-da Bai bao-chao zheng Wei Li Xiao-hui Tu School of Comprehensive Foundation Studies and Applied Statistics Zhuhai College of Jilin UniversityZhuhai 519041GuangdongChina Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou 510632China

The severely worn position and failure mechanisms of the ring die of a feed pellet machine were *** macroscopic and microscopic morphologies of the failed surface,the chemical composition and mechanical properties of the collected samples were analyzed using scanning electron microscopy,energy disperse spectroscopy,optical emission spectrometry,and a universal testing *** show that the dip angle at the entrance of the ring die hole between the roller and ring die was severely *** feed powder could not be fully extruded through the dip angle at the entrance of the ring die holes,thus the density of the feed particles produced could not meet the ***,abrasive wear under high stress is the main reason of failure at the entrance of the ring die holes under the action of feeding powder;and cutting and fatigue spalling lead to substantial material *** addition,a high damp-heat environment aggravates abrasive wear on the die hole internal surface.

关键词： ring die failure analysis micro-cutting wear fatigueexfoliative wear electrochemical corrosion

Enhanced cooperative packet retransmission employing joint cooperative diversity and symbol mapping diversity

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第8期9卷 1090-1098页

作者： Wei JI bao-yu zheng Electronic Engineering Department Shanghai Jiao Tong University Shanghai 200240 China Institute qf Signal Processing and Transmission Nanjing University of Posts ＆ Telecommunications Nanjing 210003 China

A joint cooperation diversity and symbol mapping diversity (SMD) strategy is proposed for cooperative packet retransmission system with high-order modulation such as 16QAM. Substantial SER/BER (symbol error rate/bit error rate) gains result from multiple packet transmissions over independent paths and distinct bit-to-symbol mappings for each packet transmis-sion. The SER/BER performance of relay assisted retransmission system is analyzed. Simulation results show that the joint-diversity strategy can provide more BER gains than other relaying strategies (i.e., decode-and-forward and constellation rearrangement relaying strategies) when no relay makes a decision error; but if some relays make decision errors, the joint-di-versity strategy outperforms other relaying strategies only when the relays are closer to the source than to the destination.

关键词： Cooperative retransmission Hybrid automatic repeat request (HARQ) Cooperative diversity Symbol mapping diversity (SMD)