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Group separation of coal components and new ideas of coal utilization as petroleum

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Mining Science and Technology 2009年第5期19卷 636-641页

作者： QIN Zhi-hong HOU Cui-li CHEN Juan zhang li-ying MA Jie-qiong School of Chemical Engineering and Technology China University of Mining ＆ Technology Xuzhou Jiangsu 221116 China

Four different groups of components were separated from coal under mild conditions of extraction and stripping process. Within these groups, and with pre-separation, individual utilization of all coal components can be realized, similar to petroleum components and enhance the inherent value and utilization value of coal, as well as increase environmental benefits. The characteristics of each component were analyzed with measurements by FTIR, GC/MS, TEM and the establishment of caking properties. The results show that coal can be separated into residues, ultra-pure coal, asphaltene components and light components by adding solvents for stripping into the CS2/NMP mixed extraction solution. Those four groups of components present great differences in the presence of carbon and hydrogen elements, in the structure of functional groups, in their macroscopic structure and micro-morphology and caking properties. Every component possesses its own inherent values and approaches. A new idea of coal processes and utilization, similar to the use of petroleum is proposed.

关键词： coal group components separation similarity to petroleum process and utilization

Fine Mapping and Cloning of the Grain Number Per-Panicle Gene (Gnp4) on Chromosome 4 in Rice (Oryza sativa L.)

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Agricultural Sciences in China 2011年第12期10卷 1825-1833页

作者： zhang Zhan-ying li Jin-jie YAO Guo-xin zhang Hong-liang DOU Hui-jing SHI Hong-li SUN Xing-ming li Zi-chao Key Laboratory of Crop Heterosis and Utilization Ministry of Agriculture/Beijing Key Laboratory of Crop Genetic Improvement ChinaAgricultural University Beijing 100193 P.R.China

Grain number per-panicle is one of the most important components for rice yield. Spikelets on the primary and secondary branches determine the grain number per-panicle in rice. In this study, we identified a natural mutant, gnp4, lack of lateral spikelet on the secondary branches in the field condition. In addition, the Gnp4 and Lax1-1 double mutant showed dramatically reduced secondary branches and spikelets in panicle at reproductive stage, and tillers at vegetative stage. By map-based cloning approach, and using four F2 segregating populations, the Gnp4 gene was finally mapped to a 10.7-kb region on the long arm of chromosome 4 in rice. In this region, only one gene was predicted, and genomic DNA sequencing of the 10.7-kb region showed no nucleotide differences between the mutant and wild type. Interestingly, we found that the methylation level of several cytosines in the promoter CpG islands region of the predicted gene in gnp4 were different from the wild type. Thus, we propose that the DNA methylation changes at these sites may induce to decrease expression level of Gnp4, consequently, resulting in phenotypic variation.

关键词： rice gnp4 laxl-1 grain number per-panicle methylation

Threshold Selection and Resource Allocation for Quantized Identification

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Journal of Systems Science & Complexity 2024年第1期37卷 204-229页

作者： WANG ying li Xin ZHAO Yanlong zhang Ji-Feng Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

This paper is concerned with the optimal threshold selection and resource allocation problems of quantized identification, whose aims are improving identification efficiency under limited resources. Firstly, the first-order asymptotically optimal quantized identification theory is extended to the weak persistent excitation condition. Secondly, the characteristics of time and space complexities are established based on the Cramér-Rao lower bound of quantized systems. On these basis, the optimal selection methods of fixed thresholds and adaptive thresholds are established under aperiodic signals, which answer how to achieve the best efficiency of quantized identification under the same time and space complexity. In addition, based on the principle of maximizing the identification efficiency under a given resource, the optimal resource allocation methods of quantized identification are given for the cases of fixed thresholds and adaptive thresholds, respectively, which show how to balance time and space complexity to realize the best identification efficiency of quantized identification.

关键词： Quantized output resource allocation system identification threshold selection.

The Herbicidal Activity of Mutant Isolates from Botrytis cinerea

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Agricultural Sciences in China 2006年第8期5卷 622-628页

作者： zhang Jin-lin zhang li-hui liU ying-chao MA Juan li Chuan DONG Jin-gao Mycotoxin Laboratory Hebei Agricultural University Baoding 071001 P.R.China

Fifteen mutant isolates were obtained by ultraviolet mutation from parent isolate Botrytis cinerea BC-4. Among them three mutant isolates, BC4-1, BC4-2, and BC4-15, showed strong herbicidal activity. BC4-1 showed maximum herbicidal activity for inhibition of germination and growth of Digitaria sanguinalis L. and Arnaranthus retroflexus L. The results also showed that herbicidal activity was influenced by differing pH of PD media, with pH value of 4.0 being the optimum. The crude toxin was extracted using chloroform, petroleum ether, and ethyl acetate, respectively, and the ethyl acetate extracts showed the strongest inhibitory activity on the germination and growth of D. sanguinalis L. and A. retroflexus L. Using HPLC, one fraction with an absorption peak at 271 nm was separated from the crude toxin. This fraction could strongly inhibit the growth of D. sanguinalis L. at a concentration of 100 mg L^-1 and could completely inhibit the seed germination of D. sanguinalis L. and A. retroflexus L. at a concentration of 50 mg L^-1 .

关键词： Botrytis cinerea toxin ultraviolet mutation herbicide activity separation and purification

Asymmetric synthesis of pedamide using I_2-induced heterocyclization to construct the skeleton

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Chinese Chemical Letters 2009年第7期20卷 775-778页

作者： De Gang liu Ji Jun Xue Zhi Xiang Xie li Ping Wei Hua Bing zhang ying li State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 PR China

An alternative approach to synthesize pedamide, a key building block of pederin was described. Iodine-induced asymmetric heterocyclization was used as the key step to construct the skeleton, a tetrahydropyran ring with three chiral centers. Brown＇s asymmetric allylation and Lewis acid-mediated allylation were investigated to introduce chains and chiral alcohols. Sharpless dihydroxylation decorated the side chain. And high optically pure target was obtained by removing the epimers formed in these reactions on column chromatography.C2009 Ji Jun Xue. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All fights reserved.

关键词： Synthesis Pedamide Pederin

KCTD8基因在乳腺导管内癌中的蛋白表达及临床意义

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中国现代普通外科进展 2024年第2期27卷 117-121页

作者：刘英格杨会杰翟晓玉何吉敏李鸿超张莹丽河南省濮阳市油田总医院病理科河南濮阳457001

目的:探讨KCTD8基因在乳腺导管内癌中的蛋白表达水平及其与临床因素、预后的相关性。方法:收集27例乳腺导管内癌患者癌组织和癌旁组织,应用免疫组织化学技术分析KCTD8基因在各组织中的蛋白表达水平,运用统计学方法分析KCTD8蛋白表达水... 详细信息

目的:探讨KCTD8基因在乳腺导管内癌中的蛋白表达水平及其与临床因素、预后的相关性。方法:收集27例乳腺导管内癌患者癌组织和癌旁组织,应用免疫组织化学技术分析KCTD8基因在各组织中的蛋白表达水平,运用统计学方法分析KCTD8蛋白表达水平与乳腺导管内癌患者临床因素和预后生物指标间的相关性。利用TCGA数据库分析KCTD8基因与乳腺癌(含导管内癌)预后的关系。结果:KCTD8基因在乳腺导管内癌组织中的蛋白表达水平下降(P<0.05),且其蛋白表达水平的降低与肿瘤大小相关(P<0.05)。TCGA数据库发现乳腺癌(含导管内癌)组织中KCTD8基因的表达和异常高甲基化均影响患者的预后。结论:KCTD8基因蛋白表达水平降低可能参与乳腺癌的发展,影响患者预后。

关键词：乳腺肿瘤导管内癌 KCTD8 免疫组织化学技术

Supramolecular polymer network constructed by a functionalized polyimidazolium salt derived from metal-carbene template approach

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Science China Chemistry 2024年第4期67卷 1224-1228页

作者： Ming-Ming Gan Zi-En zhang Yi-Fan zhang Heng zhang li-ying Sun ying-Feng Han Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China

In this study,we present a supramolecular templating approach for constructing polyimidazolium salt containing crown ether and cyclobutane *** strategy involves the formation of metal-carbene templates,photochemical cycloaddition,and subsequent demetallation of metal *** by the host-guest chemistry between crown ether units and ammonium salts,we successfully fabricated a supramolecular polymer SPN1,which features imidazolium receptors and cyclobutane *** obtained SPN1 demonstrates outstanding reversible stimulus-response,antibacterial behavior and conductivity.

关键词： metal-carbene template crown ether polyimidazolium salt host-guest chemistry

Solubilization of small molecules from coal and the resulting effects on the pore structure distribution

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Mining Science and Technology 2009年第6期19卷 761-768页

作者： QIN Zhi-hong JIANG Chun HOU Cui-li li Xing-shun zhang li-ying CHEN Juan JIANG Bin School of Chemical Engineering and Technology China University of Mining ＆ Technology Xuzhou Jiangsu 221116 China Lu＇an Mining Industry Group Changzhi Shanxi 046204 China

The solubilization of small molecules from coal by solvent extraction and the resulting effects on the pore distribution of a low rank coal were studied. Samples were extracted, in succession, with petroleum ether and with CS2. Extract and residue fractions collected during the solubilization process were analyzed by FTIR and by surface area and porosimetry. The results show that an obvious inflection point exists that allows separating the dissolution sequence into stages. Small molecules are first extracted from the free state, then molecules trapped in micropores are extracted and, finally, molecules trapped in the coal-matrix network are extracted. This is indicated from the extraction yield curves. Chain-like carbonyl compounds, -OH (or -NH) containing compounds that are hydrogen bonded and phenolics dominate the petroleum ether extracts. Chain-like carbonyl components and ether compounds (aliphatic ethers and aromatic ethers) dominate the CS2 extracts. A solvent dissolution mechanism and the effect of small molecule extraction on the pore structure are put forward. Diffusion, dissolution, pore opening, pore shrinking or even collapsing caused by swelling, creating of new micropores, pore opening and, finally, colloidallization of some micropores occurs. In the later stages of the extraction the internal structure of the coal is colloidallized due to swelling and the pore number or volume is greatly reduced.

关键词： coal fractional extraction FTIR distribution of pores

Efficient nitrite-to-ammonia electroreduction over Zr-Ni frustrated Lewis acid-base pairs

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Science China Chemistry 2024年第5期67卷 1707-1714页

作者： ying zhang Zhuohang li Wenyu Du Kai Chen Ke Chu School of Materials Science and Engineering Lanzhou Jiaotong UniversityLanzhou 730070China

Electrochemical NO_(2)~--to-NH_(3) conversion(NO_(2)RR) offers a green route to NH_(3) electrosynthesis, while developing efficient NO_(2)RR catalysis systems at high current densities remains a grand challenge. Herein, we report an efficient Zr-NiO catalyst with atomically dispersed Zr-dopants incorporated in NiO lattice, delivering the exceptional NO_(2)RR performance with industriallevel current density(>0.2 A cm^(-2)). In situ spectroscopic measurements and theoretical simulations reveal the construction of ZrNi frustrated Lewis acid-base pairs(FLPs) on Zr-Ni O, which can substantially increase the number of absorbed nitrite(NO_(2)~-),promote the activation and protonation of NO_(2)~- and concurrently hamper the H coverage, boosting the activity and selectivity of Zr-NiO towards the NO_(2)RR. Remarkably, Zr-NiO exhibits the exceptional performance in a flow cell with high Faradaic efficiency for NH_(3) of 94.0% and NH_(3)yield rate of 1,394.1 μmol h^(-1)cm^(-2) at an industrial-level current density of 228.2 m A cm^(-2),placing it among the best NO_(2)RR electrocatalysts for NH_(3) production.

关键词： electrochemical nitrite-to-ammonia conversion frustrated Lewis acid-base pairs(FLPs) in situ spectroscopy theoretical computations