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Devolatilization of high viscous fluids with high gravity technology

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Chinese Journal of Chemical Engineering 2024年第7期71卷 249-257页

作者： Jibing qi Youzhi liu Yandong liu Taiyuan University Taiyuan 030032China Shanxi Province Key Laboratory of Higee-Oriented Chemical Engineering North University of ChinaTaiyuan 030051China

Volatile organic compounds(VOCs)are generally toxic and harmful substances that can cause health and environmental *** removal of VOCs from polymers has become a key *** effective devolatilization to remove VOCs from high viscous fluids such as polymer is necessary and is of great *** this study,the devolatilization effect of a rotating packed bed(RPB)was studied by using polydimethylsiloxane as the viscous fluid and acetone as the *** devolatilization rate and liquid phase volume(KLa)have been *** results indicated that the optimum conditions were the high-gravity factor of 60,liquid flow rate of 10 L·h^(-1),and vacuum degree of 0.077 *** dimensionless correlation of KLa was established,and the deviations between predicted and experimental values were less than±28%.The high-gravity technology will result in lower mass transfer resistance in the devolatilization process,enhance the mass transfer process of acetone,and improve the removal effect of *** work provides a promising path for the removal of volatiles from polymers in combination with high-gravity *** can provide the basis for the application of RPB in viscous fluids.

关键词： High-gravity technology Devolatilization rate High viscous fluid Volatile organic compounds(VOCs)

The alkynyl-containing compounds from mushrooms and their biological activities

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Natural Products and Bioprospecting 2023年第1期13卷 138-158页

作者： Ji-shuang qi Yingce duan Zhao-chen Li Jin-ming Gao Jianzhao qi Chengwei liu Key Laboratory for Enzyme and Enzyme-Like Material Engineering of Heilongjiang College of Life ScienceNortheast Forestry UniversityHarbin 150040China Shaanxi Key Laboratory of Natural Products&Chemical Biology College of Chemistry&PharmacyNorthwest A&F UniversityYangling 712100China

Mushrooms have been utilized by humans for thousands of years due to their medicinal and nutritional *** are a crucial natural source of bioactive secondary metabolites,and recent advancements have led to the isolation of several alkynyl-containing compounds with potential medicinal *** their relatively low abundance,naturally occurring alkynyl compounds have attracted considerable attention due to their high *** studies have shown that alkynyl compounds exhibit significant biological and pharmacological activities,including antitumor,antibacterial,antifungal,insecticidal,phototoxic,HIV-inhibitory,and immunosuppressive *** review systematically compiles 213 alkynyl-containing bioactive compounds isolated from mushrooms since 1947 and summarizes their diverse biological activities,focusing mainly on cytotoxicity and anticancer *** review serves as a detailed and comprehensive reference for the chemical structures and bioactivity of alkynyl-containing secondary metabolites from ***,it provides theoretical support for the development of chemical constituents containing alkynyl compounds in mushrooms based on academic research and theory.

关键词： Mushroom Alkynyl compounds Bioactivity Chemical structures

Modified fast Fourier transform in FBMC for satellite communications

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Chinese Journal of Aeronautics 2017年第4期30卷 1519-1527页

作者： Chaosan YANG Rongke liu Ruifeng duan School of Electronic and Information Engineering Beihang University School of Information Science and Technology Beijing Forestry University

In this paper,a Doppler scaling fast Fourier transform（Doppler-FFT）algorithm for filter bank multi-carrier（FBMC）is proposed,which can efficiently eliminate the impact of the Doppler scaling in satellite *** introducing a Doppler scaling factor into the butterfly structure of the fast Fourier transform（FFT）algorithm,the proposed algorithm eliminates the differences between the Doppler shifts of the received subcarriers,and maintains the same order of computational complexity compared to that of the traditional *** the process of using the new method,the Doppler scaling should be estimated by calculating the orbital data in ***,the inter-symbol interference（ISI）and the inter-carrier interference（ICI）can be completely eliminated,and the signal to interference and noise ratio（SINR）will not be *** results also show that the proposed algorithm can achieve a 0.4 d B performance gain compared to the frequency domain equalization（FDE）algorithm in satellite communications.

关键词： Doppler effect Fast Fourier transforms Filter bank multi-carrier Inter-carrier interference Inter-symbol interference Signal to interference and noise ratio

Characteristics and source identification of fine particulate n-alkanes in Beijing, China

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Journal of Environmental Sciences 2010年第7期22卷 998-1005页

作者： Fengkui duan Kebin He Xiande liu State Key Joint Laboratory of Environment Simulation and Pollution Control Department of Environmental Science & Engineering Tsinghua University Beijing 100084 China Chinese Research Academy of Environmental Sciences Beijing 100012 China

Ambient particulate n-alkanes were determined for fine particle （PM2.5） samples collected from Sep 2003 to July 2004 in Beijing, China. The average concentration of total n-alkanes （∑n-alkanes） from Cll to C34 was 425.72 ng/m^3, ranged from 7.02 to 2893.28 ng/m^3. The concentration distributions of n-alkanes homologues in this study exhibited peaks at C21 and C29 in heating season, and C29 in non-heating season. The average carbon preference index （CPI） value was 1.88 in the range of 1.18-3.88. The maximum CPI in summer indicated the contribution of biogenic origins such as plant wax; while the minimum CPI value in winter was probably a result of fossil fuel combustion. Preliminary estimation from these results showed that 59% of the n-alkanes in PM2.5 in Beijing summer originated from plant wax, while 74%-88% was from fossil fuel combustion in other three seasons. Source estimation was further performed using principal component analysis method. Two major components were yielded accounting for 57.3% and 30.9% of the total variance, which presented the fossil fuel and biogenic contribution, respectively.

关键词： n-alkanes PM2.5 carbon preference index principal component analysis

Lacustrine shale oiliness influenced by diabase intrusions in the Paleogene Funing Formation,Subei Basin,China

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Petroleum Science 2023年第5期20卷 2683-2694页

作者： Biao Sun Xiao-Ping liu Jie liu qi-Dong liu Hong-Liang duan Shi-Li liu Ming Guan Tian liu Zu-Xian Hua Kai Sheng Yu-Jie Xing State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China International Petroleum Exploration and Production Corporation SINOPECBeijing100029China Research Institute of Exploration and Development SINOPEC Jiangsu Oilfield CompanyJiangsu225009China

The research on the correlation between hydrocarbon accumulations and magmatic activities has always attracted aroused much wide *** research has primarily the hydrocarbon generations capability of source rocks and the quality of reservoirs by diabase ***,rare systematic research has been conducted on the oiliness and enrichment *** be specific,the diabase intrusive zone,the contact metamorphic zone and the normal shale zone of the Funing Formation in the Gaoyou Sag,Subei Basin were taken as the object of this ***,in this study,the hydrocarbon generation quality,reservoir quality,and oil-bearing quality of diabase-metamorphic zone-normal shale were evaluated using X-ray diffractions,argon ion polishing-field emission scanning electron microscope,energy spectrum,rock slice/light-sheet microscopic observations,organic geochemical tests,N_(2) gas adsorption and 2D NMR *** results indicated that the intrusive zone,the metamorphic zone,and the normal zone were formed in order by the degree of effect of diabase ***,the oil content of different parts exhibited significant heterogeneity due to the baking effect of diabase,and the metamorphic zone had the significantly better oil-bearing nature than the intrusive ***,a distribution model was proposed for the diabase intrusive zone-metamorphic zone-normal surrounding rock zone.

关键词： Shale reservoirs Diabase intrusion Oiliness Funing formation

Parametric control of quasi-linear second-order systems with partitioned eigenstructure assignment by output feedback

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Science China(Information Sciences) 2023年第4期66卷 228-243页

作者： Weizhen liu Guangren duan Dake GU Center for Control Theory and Guidance Technology Harbin Institute of Technology Center for Control Science and Technology Southern University of Science and Technology School of Automation Engineering Northeast Electric Power University

In this paper, a parametric design approach for stabilizing a quasi-linear second-order system with partitioned eigenstructure assignment(PESA) is investigated through output feedback control. The PESA approach is established by partitioning the desired eigenvalue matrix into two parts to separate the associated right and left eigenvectors into a subset of the generalized eigenvectors simultaneously. A parametric controller is established by solving two second-order generalized Sylvester matrix equations, and a certain form with the desired eigenstructure can be derived with the established quasi-linear output feedback controller. Unlike the prevailing approach that assigns the entire set of generalized eigenvectors, which is difficult to satisfy a large number of complicated constraints in practical systems by the normalized pair of right and left eigenvector matrices, a subset of the generalized eigenvectors is considered. In addition, the proposed PESA approach provides less computational load and is easy to use. A numerical example and application in spacecraft rendezvous are provided to verify the numerical economy and high efficiency of the proposed approach.

关键词： quasi-linear second-order systems partitioned eigenstructure assignment parametric approach Sylvester matrix equation output feedback

Distinguishing unitary gates on the IBM quantum processor

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Science China(Information Sciences) 2019年第7期62卷 210-216页

作者： Shusen liu Yinan LI Runyao duan School of Data and Computer Science Sun Yat-sen University Centre for Quantum Software and Information Faculty of Engineering and Information TechnologyUniversity of Technology Sydney

An unknown unitary gate, which is secretly chosen from several known ones, can always be distinguished perfectly. In this paper, we implement such a task on IBM’s quantum processor. More precisely,we experimentally demonstrate the discrimination of two qubit unitary gates, the identity gate and the 2/3π-phase shift gate, using two discrimination schemes — the parallel scheme and the sequential scheme. We program these two schemes on the ibmqx4, a 5-qubit superconducting quantum processor via IBM cloud,with the help of the QSI modules. We report that both discrimination schemes achieve success probabilities at least 85%.

关键词： quantum experiment IBM quantum computer software-aided quantum experiment sequential schemes for unitary discrimination parallel schemes for unitary discrimination

Lake inventory and potentially dangerous glacial lakes in the Nyang Qu Basin of China between 1970 and 2016

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Journal of Mountain Science 2020年第4期17卷 851-870页

作者： qi Miao-miao liu Shi-yin YAO Xiao-jun Richard Grünwald GAO Yong-peng duan Hong-yu liu Juan Institute of International Rivers and Eco-Security Yunnan UniversityKunming 650091China Yunnan Key Laboratory of International Rivers and Transboundary Eco-security Kunming 650091China College of Geography and Environment Sciences Northwest Normal UniversityLanzhou 730070China

There are a large number of glaciers and lakes developed in the Nyang Qu Basin of China. Recent climate change has significant impacted on the high-mountain glacial environment. Rapid melting of glaciers contributes to the formation and expansion of moraine-dammed lakes which increase the probability of glacial lake outburst floods(GLOFs). We calculated a multi-temporal lake inventory based on(1) topographic maps in the 1970 s,(2) satellite imageries from 1990 to 2016,(3) First Chinese Glacier Inventory(FCGI),(4) Glacier Inventory of Southeastern Tibet(GIST) and(5) meteorological data. A total of 880 lakes(>0.01 km^2) have been mapped in 2016, with 318 being glacial lakes(GLs) and 462 non-glacier lakes(NGLs). Most of the lakes were mainly located at 4500 m a.s.l. and the lakes dominated by small lakes(<0.1 km^2) where the change of their actual sizes are more significant compared to the larger ones. Meanwhile, we found that there were 178 newly formed GLs and 51 of them had disappeared between 1970 and 2016. During the same period, there can be identified 157 newly formed GLs and 226 had disappeared. We additionally performed a hazard and risk assessment for GL in 2016 and exposed 14 potentially dangerous morainedammed lakes(PDMDLs), covering a total area of 5.88 km2 in the Nyang Qu Basin. There can be found 4 GLs with very high risk, 3 GLs with high risk, 4 GLs with medium risk and 4 GLs with low risk of GLOFs susceptibility. The findings of this study can be used for the future policy of risk management and also be adapted for promoting water resources management.

关键词： Lake Inventory Potentially dangerous moraine-dammed lakes(PDMDLs) Hazard assessment Tibetan Plateau Nyang Qu Basin

A Gaussian copula regression model for movie box-office revenues prediction

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Science China(Information Sciences) 2017年第9期60卷 36-49页

作者： Junwen duan Xiao DING Ting liu Research Center for Social Computing and Information Retrieval Harbin Institute of Technology

In this article, we revisit the task of movie box-office revenues prediction using multi-type *** movie box-office revenues are affected by numerous factors. Previous work with discriminative models assumes these factors are identically and independently distributed. The correlations between these factors are rarely considered, which limited the performances of discriminative models in this task. To address these problems, we investigate a novel Gaussian copula regression model. Based on this model, we do not need to make any prior assumptions about the marginal distributions of the features. In particular, we perform a cumulative probability estimation on each of the smoothed features. The estimation learns the marginal distributions and maps all features into a uniform vector space. Sequentially, we bridge the marginal distributions with a copula function to create their joint distribution, and learn the dependency structure between them. Moreover, we propose a computational-efficient approximate algorithm for responsible variable inference. Experimental results on two movie datasets from Chinese and U.S. market show that our approach outperforms strong discriminative regression baselines.

关键词： Gaussian copula movie box-office revenue multi-variate regression text regression social media