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Influence of Gas Components on the Formation of Carbonyl Sulfide over Water-Gas Shift Catalyst B303Q

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Journal of Natural Gas Chemistry 2007年第1期16卷 53-59页

作者： Ju Shangguan Litong Liang Huiling fan fang Shen Key Laboratory of Coal Science and Technology Taiyuan University of Technology Ministry of Education and Shanxi Province Taiyuan 030024 Shanxi China

Water-gas shift reaction catalyst at lower temperature （200-400 ℃） may improve the conversion of carbon monoxide. But carbonyl sulfide was found to be present over the sulfided cobaltmolybdenum/alumina catalyst for water-gas shift reaction. The influences of temperature, space velocity, and gas components on the formation of carbonyl sulfide over sulfided cobalt-molybdenum/alumina catalyst B303Q at 200-400 ℃ were studied in a tubular fixed-bed quartz-glass reactor under simulated water-gas shift conditions. The experimental results showed that the yield of carbonyl sulfide over B303Q catalyst reached a maximum at 220 ℃ with the increase in temperature, sharply decreased with the increase in space velocity and the content of water vapor, increased with the increase in the content of carbon monoxide and carbon dioxide, and its yield increased and then reached a stable value with the increase in the content of hydrogen and hydrogen sulfide. The formation mechanism of carbonyl sulfide over B303Q catalyst at 200-400 ℃ was discussed on the basis of how these factors influence the formation of COS. The yield of carbonyl sulfide over B303Q catalyst at 200-400 ℃ was the combined result of two reactions, that is, COS was first produced by the reaction of carbon monoxide with hydrogen sulfide, and then the as-produced COS was converted to hydrogen sulfide and carbon dioxide by hydrolysis. The mechanism of COS formation is assumed as follows： sulfur atoms in the Co9Ss-MoS2/Al2O3 crystal lattice were easily removed and formed carbonyl sulfide with CO, and then hydrogen sulfide in the water-gas shift gas reacted with the crystal lattice oxygen atoms in CoO-MoOa/Al2O3 to form Co9S8-MoS2/Al2O3. This mechanism for the formation of COS over water-gas shift catalyst B303Q is in accordance with the Mars-Van Krevelen＇s redox mechanism over metal sulfide.

关键词： formation carbonyl sulfide sulfided cobalt-molybdenum/alumina catalyst water-gas shift

Statistical properties of random clique networks

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Frontiers of physics 2017年第5期12卷 251-257页

作者： Yi-Min Ding Jun Meng Jing-fang fan fang-Fu Ye Xiao-Song Chen Faculty of Physics and Electronics Hubei University Wuhan 430062 China CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences P.O. Box 2735 Beijing 100190 China Beijing National Laboratory for Condensed Matter Physics CAS Key Laboratory of Soft Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing 100049 China

In this paper, a random clique network model to mimic the large clustering coefficient and the modular structure that exist in many real complex networks, such as social networks, artificial networks, and protein interaction networks, is introduced by combining the random selection rule of the ErdSs and Rényi （ER） model and the concept of cliques. We find that random clique networks having a small average degree differ from the ER network in that they have a large clustering coefficient and a power law clustering spectrum, while networks having a high average degree have similar properties as the ER model. In addition, we find that the relation between the clustering coefficient and the average degree shows a non-monotonic behavior and that the degree distributions can be fit by multiple Poisson curves; we explain the origin of such novel behaviors and degree distributions.

关键词： complex networks random clique networks motifs communicability

A microcosmic discrete occupant evacuation model based on individual characteristics

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Science China(Technological Sciences) 2004年第5期47卷 608-615页

作者： YANG Lizhong LI Jian ZHAO Daoliang fang Weifeng fan Weicheng State Key Laboratory of Fire Science University of Science and Technology of China Hefei 230026 China State Key Laboratory of Fire Science University of Science and Technology of China Hefei 230026 China State Key Laboratory of Fire Science University of Science and Technology of China Hefei 230026 China State Key Laboratory of Fire Science University of Science and Technology of China Hefei 230026 China State Key Laboratory of Fire Science University of Science and Technology of China Hefei 230026 China

The research of occupant evacuation in an emergency is of great benefit to building design and evacuation guidance. In this paper a microcosmic discrete evacuation model based on Cellular Automata (CA) is presented, in which the occupants?individual characteristics are considered. Thus, our model has given a description of evacuation route choice with influencing factors, including: individual knowledge of the building, individual realization of the emergency development, and the attractive and repulsive force between occupants. This model differs somewhat from other models in the attention to the associative and separate effect of influencing factors, based on occupants behaviors. In addition, the model could reveal the phenomenon of escape in fire, as those simulations involving a fire condition have shown.

关键词： evacuation, cellular automata, microcosmic discrete model, occupant behavior, fire.

Combined use of an alkene and a phosphine as a nucleophilic catalyst system for the cyanosilylation of carbonyl compounds

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Chinese Science Bulletin 2010年第25期55卷 2820-2823页

作者： WANG Xiu fang fan TIAN ShiKai Department of Chemistry University of Science and Technology of China Hefei 230026 China

The catalytic potential of carbon nucleophiles has seldom been disclosed due to their reactivity toward carbon electrophiles to form stable carbon-carbon bonds,which are too strong to be cleaved for the expected catalytic cycles. We have developed an efficient catalytic cyanosilylation of carbonyl compounds with an in situ generated alkene/phosphine adduct,which is tuned not to couple with a carbonyl compound or an electron-deficient alkene under the reaction conditions when its nucleophilicity is trans-lated into catalytic activity. In the presence of 3 mol% of methyl acrylate and 3 mol% of triphenylphosphine,a broad range of alkyl,alkenyl,and aryl ketones and aldehydes undergo cyanosilylation reaction with trimethylsilyl cyanide at room temperature to yield structurally diversified cyanohydrin silyl ethers in excellent yields. By using methyl acrylate/triphenylphosphine as a highly effective nucleophilic catalyst system for the cyanosilylation of carbonyl compounds,this study demonstrates a new concept for the development of useful organocatalysis utilizing the nucleophilicity of alkene/phosphine adducts generated in situ.

关键词：羰基化合物亲核试剂催化体系烯烃联合使用磷化氢甲基丙烯酸酯三苯基膦

Liquid-encapsulated quantum dot for enhanced UV and thermal stability of quantum dot color conversion films

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Nano Research 2024年第11期17卷 10127-10133页

作者： Ronghuan Liu fan fang Pai Liu Xijian Duan Kai Wang Xiao Wei Sun Institute of Nanoscience and Applications and Department of Electrical and Electronic Engineering Southern University of Science and Technology Shenzhen 518055 China Key Laboratory of Energy Conversion and Storage Technologies (Southern University of Science and Technology) Ministry of Education and Shenzhen Key Laboratory for Advanced Quantum Dot Displays and Lighting Southern University of Science and Technology Shenzhen 518055 China

Encapsulation is a widely recognized method for enhancing the stability of colloidal quantum dots (CQDs). However, traditional encapsulation methods for solid-state materials expose encapsulated CQDs to risks such as ligand loss and poor dispersion. Additionally, these encapsulated CQDs still face the risk of aging due to surface ligand bond breakage under high-energy radiation. In this study, we found that quantum dots in solution exhibited enhanced ultraviolet (UV) tolerance compared to their counterparts in solid form under an inert atmosphere. We attribute this enhancement to improved ligand retention and self-healing of quantum dots in solution. Herein, we introduce a novel method for fabricating liquid-encapsulated quantum dot (LEQD) color conversion films. This technique leverages the self-healing capability of ligands in liquid-state quantum dots to enhance the UV and thermal stability of the quantum dot color conversion films. Experimental results demonstrate that LEQD films exhibit better resistance to UV radiation and high temperatures than solid-encapsulated quantum dot (SEQD) color conversion films. After 400 h of exposure to 100 mW blue light-emitting device (LED) light at 60 °C and 90% humidity, the brightness of LEQD film retained 90% of its initial level. This liquid-state quantum dot encapsulation approach offers a promising pathway for developing more durable quantum dot color conversion films.

关键词： liquid encapsulation quantum dots stability quantum dot color conversion film

Effect of enalapril on plasma homocysteine levels in patients with essential hypertension

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第8期11卷 583-591页

作者： fang-fang fan Yong HUO Xu WANG Xin XU Bin-yan WANG Xi-ping XU Jian-ping LI Department of Cardiology Peking University First Hospital Beijing 100034 China Institute of Biomedicine Anhui Medical University Hefei 230032 China

Objective:To investigate the effect of enalapril on plasma homocysteine(Hcy) levels and the association of methylenetetrahydrofolate reductase(MTHFR) C677T polymorphism with the changes of Hcy levels in response to enalapril among patients with essential ***:A total of 130 patients with mild-to-moderate essential hypertension were enrolled and enalapril was orally administered at a dose of 10 mg/d for eight *** Hcy levels were measured by denaturing high-performance liquid chromatography(DHPLC) at baseline and after eight weeks of *** of MTHFR C677T polymorphism was performed by TaqMan probe ***:Compared with baseline,plasma Hcy levels did not change significantly after eight weeks(P=0.81).Stratified by baseline Hcy levels,a significant increase in plasma Hcy levels(P=0.02) among those with Hcy <10 μmol/L was observed,in contrast to no significant changes in plasma Hcy levels(P=0.54) among those with Hcy ≥10 μmol/*** significant association was observed between MTHFR C677T polymorphism and changes in Hcy levels in response to ***:Enalapril may cause an increase in plasma Hcy levels among the hypertensives with low baseline Hcy *** was no significant association between MTHFR C677T genotypes and changes in Hcy levels in response to enalapril among subjects with essential hypertension.

关键词： Essential hypertension Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism Enalapril Homocysteine

Improving sentiment analysis accuracy with emoji embedding

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Journal of Safety Science and Resilience 2021年第4期2卷 246-252页

作者： Chuchu Liu fan fang Xu Lin Tie Cai Xu Tan Jianguo Liu Xin Lu College of Systems Engineering National University of Defense TechnologyChangsha410073China College of Computer National University of Defense TechnologyChangsha410073China School of Software Engineering Shenzhen Institute of Information TechnologyShenzhen518172China Institute of Accounting and Finance Shanghai University of Finance and EconomicsShanghai200433China

Due to the diversity and variability of Chinese syntax and semantics,accurately identifying and distinguishing individual emotions from online texts is *** overcome this limitation,we incorporate a new source of individual sentiment,emojis,which contain thousands of graphic symbols and are increasingly being used for expressing emotion in online *** examined popular sentiment analysis algorithms,including rule-based and classification algorithms,to evaluate the impact of supplementing emojis as additional features to improve the algorithm *** were also translated into corresponding sentiment words when con-structing features for comparison with those directly generated from emoji label *** addition,considering different functions of emojis in texts,we classified all posts in the dataset by their emoji usage and examined the changes in algorithm *** found that emojis are effective as expanding features for improving the accuracy of sentiment analysis algorithms,and the algorithm performance can be further increased by taking different emoji usages into *** this study,we developed an improved emoji-embedding model based on Bi-LSTM(namely,CEmo-LSTM),which achieves the highest accuracy(around 0.95)when analyzing online Chinese *** applied the CEmo-LSTM algorithm to a large dataset collected from Weibo from December 1,2019 to March 20,2020 to understand the sentiment evolution of online users during the COVID-19 *** found that the pandemic remarkably impacted individual sentiments and caused more passive emotions(e.g.,horror and sadness).Our novel emoji-embedding algorithm creatively combined emojis as well as emoji usage with the sentiment analysis model and can handle emotion mining tasks more effectively and efficiently.

关键词： Sentiment analysis Emoji CEmo-LSTM Sentiment evolution COVID-19

Thirty-day outcomes of in-hospital multi-vessel versus culpritonly revascularization strategy for ST-segment elevation myocardial infarction with multivessel coronary disease

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Journal of Geriatric Cardiology 2023年第7期20卷 485-494页

作者： Yu-Xi LI Bei-Ning WANG fang-fang fan Yan ZHANG Jie JIANG Jian-Ping LI Ya-Ling HAN Yong Huo CCC investigators Department of Cardiology Peking University First HospitalBeijingChina Cardiovascular Research Institute and Department of Cardiology General Hospital of Northern Theater CommandShenyangLiaoningChina 不详

BACKGROUND Many studies have demonstrated the benefit of complete multivessel revascularization versus culprit-only intervention in patients of ST-segment elevation myocardial infarction(STEMI)and multivessel coronary artery ***,only a few single-center retrospective studies were performed on small Chinese *** study aims to demonstrate the advantage of multivessel percutaneous intervention(PCI)strategy on 30-day in-hospital outcomes to patients with STEMI and multivessel disease in larger Chinese *** From the Improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome(CCC-ACS)project,5935 patients with STEMI and multivessel disease undergoing PCI and hospitalized for fewer than 30 days were *** 5:1 propensity score matching,3577 patients with culprit-only PCI and 877 with in-hospital multivessel PCI were *** primary outcome was major adverse cardiovascular and cerebrovascular event(MACCE),defined as a composite of myocardial infarction,all-cause death,stent thrombosis,heart failure,and *** Multivariable logistic regression analysis revealed that in-hospital multivessel PCI was associated with lower risk of 30-day MACCE(adjusted OR=0.75,95%CI:0.57-0.98,P=0.032)than culprit-only PCI and conferred no increased risk of allcause death,myocardial infarction,stent thrombosis,stroke,or *** analysis showed that MACCE reduction was observed more often from patients with trans-femoral access(OR=0.34,95%CI:0.15-0.74)than with trans-radial access(OR=0.87,95%CI:0.66-1.16,P for interaction=0.017).CONCLUSIONS The in-hospital multivessel PCI strategy was associated with a lower risk of 30-day MACCE than culprit-only PCI in patients with STEMI and multivessel coronary artery disease.

关键词： infarction coronary myocardial

Comparison of the efficacy and safety of ultrasonic cycloplasty vs valve implantation and anti-VEGF for the treatment of fundus disease-related neovascular glaucoma

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International Journal of Ophthalmology(English edition) 2023年第6期16卷 897-903页

作者： fang-fang fan Xing Ge Dan-Dan Liu Teng-Yu Xu Rui-Xue Wang Xiao-Ya Chen Su-Yan Li The Affiliated Xuzhou Municipal Hospital of Xuzhou Medical University Xuzhou 221000Jiangsu ProvinceChina Department of Ophthalmology Xuzhou First People’s HospitalXuzhou 221000Jiangsu ProvinceChina Eye Disease Prevention and Treatment Institute of Xuzhou Xuzhou 221000Jiangsu ProvinceChina

·AIM: To compare the clinical efficacy and safety of ultrasonic cycloplasty(UCP) vs Ahmed glaucoma drainage valve implantation(ADV) in addition to intravitreal antivascular endothelial growth factor(VEGF) for treatment of fundus disease-related neovascular glaucoma(NVG).·METHODS: A total of 43 patients(45 eyes) with NVG secondary to fundus diseases underwent anti-VEGF combined with UCP or ADV from August 2020 to March 2022 were enrolled in this retrospective cohort study. Of them, 14 patients(15 eyes) were treated with both UCP and anti-VEGF as the UCP group and 29 patients(30 eyes) treated with both ADV and anti-VEGF as the ADV group. The success of the treatment was defined as intraocular pressure(IOP) between 11-20 mm Hg with or without using IOP-lowering drugs. IOP measurement, IOP lowering drugs at baseline and follow-ups period and complications were recorded.·RESULTS: The average age was 63.03±9.95 and 52.27±12.89y in ADV and UCP groups, respectively(P=1.947). The fundus pathology included proliferative diabetic retinopathy in 42 eyes and retinal vein occlusion in 3 eyes. All eyes in both groups achieved successful treatment at 3mo. While the success rate was 90.0%(27/30) in the ADV group and 86.7%(13/15) in the UCP group at the last follow-up of 6mo(P>0.05). IOP was significantly lower with reduction of drug use than the baseline in both groups(both P<0.05). And the ADV group needed fewer anti-glaucoma drops than the UCP group from 1d to 3mo. The comfort scores of patients in the ADV group were significantly lower than those in the UCP group in the first week after the operation(P<0.05).·CONCLUSION: UCP is an alternative to the ADV with the same efficacy but non-invasive for the treatment of NVG.

关键词： ultrasound cycloplasty Ahmed glaucoma drainage valve implantation anti-vascular endothelial growth factor neovascular glaucoma intraocular pressure