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A gram-scale synthesis of multi-substituted arenes via palladium catalyzed C–H halogenation

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Chinese Chemical Letters 2014年第5期25卷 667-669页

作者： Xiu-Yun sun Yong-hui sun Yu Rao MOE Key Laboratory of Protein Sciences Department of Pharmacology and Pharmaceutical SciencesSchool of Medicine and School of Life SciencesTsinghua University

（6-Amino-2-chloro-3-fluorophenyl）methanol is prepared through both traditional methods and palladium catalyzed iterative C–H halogenation *** comparison to traditional approach,the C–H functionalization strategy demonstrated a few advantages including milder reaction conditions higher yields,better selectivity and practicality,and high chemical diversity.

关键词： Palladium catalysis C–H halogenation Substituted arenes

Hashing multiple messages with SM3 on GPU platforms

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Science China(Information Sciences) 2021年第9期64卷 241-243页

作者： Shuzhou sun Rui ZHANG hui MA State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of Sciences School of Cyber Security University of Chinese Academy of Sciences

Dear editor,The SM3 cryptographic hash algorithm [1] was approved as the only standard hash function in China and standardized as a Chinese National Standard(GB standard) in2016. Soon after, SM3 was standardized by the International Organization for Standardization(ISO). The structure of SM3 is similar to SHA-2 family [2], which based on the Merkle-Damg°ard construction, with the addition of several strengthening features including a more complex step function and stronger message dependency than SHA-2.

关键词： SM3 Hash algorithm Parallel computation GPU High performance implementation

Distributed optimal consensus of second-order multi-agent systems

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Science China(Information Sciences) 2021年第10期64卷 248-250页

作者： hui sun Yungang LIU Fengzhong LI School of Control Science and Engineering Shandong University

Dear editor,For multi-agent systems, consensus is the most fundamental problem, for which, vast studies have been reported, but a few achieved optimal protocols [1–9]. As well known, optimal consensus is nontrivial due to the mismatching between the whole performance optimization(which usually leads to a centralized protocol) and the given distributed communication topology [1].

关键词： Multi-agent systems Leader-following Consensus Global optimization Distributed optimal protocol

Holographic heat engine efficiency of hyperbolic charged black holes

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Chinese Physics B 2021年第10期30卷 719-723页

作者： Wei sun Xian-hui Ge Department of Physics Shanghai UniversityShanghai 200444China

We consider a four-dimensional charged hyperbolic black hole as working matter to establish a black hole holographic heat engine,and use the rectangular cycle to obtain the heat engine *** find that when the increasing of entropy is zero,the heat engine efficiency of the hyperbolic black hole becomes the well-known Carnot *** also find that less charge corresponds to higher efficiency in the case of˜q>***,we study the efficiency of the flat case and spherical case and compare the efficiency with that of the hyperbolic charged black ***,we use numerical simulation to study the efficiency in benchmark scheme.

关键词： holographic heat engines benchmark cycle hyperbolic charged black holes

Dyes adsorption using a synthetic carboxymethyl cellulose-acrylic acid adsorbent

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Journal of Environmental Sciences 2014年第5期26卷 1203-1211页

作者： Genlin Zhang Lijuan Yi hui Deng Ping sun School of Chemistry and Chemical Engineering Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan Shihezi University

Removal of noxious dyes is gaining public and technological attention. Herein grafting polymerization was employed to produce a novel adsorbent using acrylic acid and carboxymethyl cellulose for dye removal. Scanning electron microscopy and Fourier-transform infrared spectroscopy verified the adsorbent formed under optimized reaction conditions. The removal ratio of adsorbent to Methyl Orange, Disperse Blue 2BLN and malachite green chloride reached to 84.2%, 79.6% and 99.9%, respectively. The greater agreement between the calculated and experimental results suggested that pseudo second-order kinetic model better represents the kinetic adsorption data. Equilibrium adsorptions of dyes were better explained by the Temkin isotherm. The results implied that this new cellulose-based absorbent had the universaiity for removal of dyes through the chemical adsorption mechanism.

关键词： adsorption dye grafting polymerization carboxymethyl cellulose acrylic acid

Distribution of phytoplankton community and its influence factors in an urban river network,East China

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Frontiers of Environmental Science & Engineering 2018年第6期12卷 133-144页

作者： Ling sun hui Wang Yuanqing Kan Shiliang Wang State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Tianjin Key Laboratory of Animal and Plant Resistance College of Life SciencesTianjin Normal UniversityTianjin 300387China Tianjin Academy of Environmental Sciences Tianjin 300191China School of Geography and Tourism Qufu Normal UniversityRizhao 276826China

To reveal the distribution characteristics of phytoplankton and the main influence factors under different conditions in the urban rivers, the investigations were conducted during autumn and winter 2014 in Changzhou City, East China. 178 taxa of phytoplankton belonging to 28 functional assemblages were identified. In autumn, the phytoplankton community compositions have high similarity for enhanced hydrological connectivity. The chlorophytes and diatoms (prevailing functional groups C, F, J, P), together with euglenoids (W1), showed high proportions of biomass in the main rivers and connected rivers. It was related to the well mixed eutrophic conditions. The phytoplankton community exhibited spatiotemporal heterogeneity in winter. Affected by the low water level and temperature, the free-living phytoflagellates (X2) replaced groups F and J in the main rivers. Phytoplankton productivity was the highest in the Tongji River. Chlorophytes Dictyosphaerium ehrenbergianum and Chlamydobotrys stellata had an overwhelming superiority during the winter bloom. They were significantly correlated with ammonium, total phosphorus and biochemical oxygen demand. Affected by tail water supply, the diatoms (MP) and euglenoids (W1) dominated in a beheaded river. The multivariate analyses based on the phytoplankton functional groups helped to evaluate the relationships and variations between the urban rivers. The redundancy analysis (RDA) results showed that nitrate nitrogen, water temperature, total nitrogen and total suspended solids were the main influence factors on the phytoplankton community. Except MP, the prevailing groups all showed significant negative correlations with nitrate nitrogen. Availability and utilization of dissolved inorganic nitrogen and hydrodynamic conditions affected the phytoplankton distribution.

关键词： Phytoplankton composition Spatiotemporal distribution Functional groups Nitrate nitrogen Winter bloom

Sensor fault-tolerant observer applied in UAV anti-skid braking control under control input constraint

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Journal of Systems Engineering and Electronics 2017年第1期28卷 126-136页

作者： hui sun Jianguo Yan Yaohong Qu Jie Ren School of Automation Northwestern Polytechnical University Chengdu aircraft Industrial (Group) Co. Ltd.

This paper proposes a method for addressing the problem of sensor fault-tolerant control (FTC) for anti-skid braking systems (ABSs). When the wheel velocity sensor of the ABS for unmanned aerial vehicles (UAVs) becomes faulty, wheel velocity failure and feedback instability may occur. Firstly, a fault diagnosis and isolation (FDI) method based on a sliding mode observer approach is introduced to detect and isolate the fault of the sensor. When the wheel velocity sensor is in healthy conditions, the observer works in a diagnosis mode. If faults occur in the sensor, it acts as a wheel velocity estimator. Secondly, an FTC strategy, adopting a feedback compensation structure, is designed with input control constraints. In addition, based on the FDI result, a terminal sliding mode (TSM) controller is designed to guarantee that slip-ratio tracks its appropriate reference values in situations where runways change conditions during landing. The control system switches automatically from control using a wheel velocity sensor to sensorless control mode, so the observer-based FTC scheme is established. It is logical that the ABS keeps observed-state and remains stable when the wheel velocity sensor is broken and during external disturbance. Finally, simulation results show the effectiveness of the proposed method. © 1990-2011 Beijing Institute of Aerospace Information.

关键词： Braking Control systems Failure analysis Fault tolerance Feedback Sensorless control Sliding mode control Unmanned aerial vehicles (UAV) Velocity Wheels

Experimental Study on Thermal Performance of FLNG Spiral Wound Heat Exchanger under Sloshing Conditions

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Journal of Thermal Science 2019年第5期28卷 1042-1053页

作者： YAN Yan sun Chongzheng HAN hui LI Yuxing College of Pipeline and Civil Engineering/Shandong Provincial Key Laboratory of Oil & Gas Storage and Transportation Safety/Qingdao Key Laboratory of Circle Sea Oil & Gas Storage and Transportation Technology China University of Petroleum

The FLNG spiral wound heat exchanger(SWHE) is affected by the sea conditions, which leads to more complex flow process and decrease the heat transfer performance of the heat exchanger. In order to study the thermal performance of FLNG SWHE under heaving and swaying conditions, the experimental devices of FLNG SWHE and six-DOF(degree of freedom) sloshing platform were built. The effects of heaving and swaying motions on the pressure drop and heat transfer characteristics were analyzed at different sloshing amplitudes. The results showed that the heaving and swaying motions can cause the temperature rise and pressure fluctuation of SWHE, especially for swaying. The effect of sloshing on the heat transfer performance at the top of SWHE was greater than bottom. The pressure fluctuation percentage was within 7% and the amount of temperature change was less than 2℃, under the sloshing displacement among 120–255 mm.

关键词： spiral wound heat exchanger FLNG experimental sloshing

Solar fuel from photo-thermal catalytic reactions with spectrum-selectivity： a review

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Frontiers in Energy 2017年第4期11卷 437-451页

作者： Sanli TANG Jie sun hui HONG Qibin LIU Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Solar fuel is one of the ideal energy sources in the future. The synergy of photo and thermal effects leads to a new approach to higher solar fuel production under relatively mild conditions. This paper reviews different approaches for solar fuel production from spectrum- selective photo-thermal synergetic catalysis. The review begins with the meaning of synergetic effects, and the mechanisms of spectrum-selectivity and photo-thermal catalysis. Then, from a technical perspective, a number of experimental or theoretical works are sorted by the chemical reactions and the sacrificial reagents applied. In addition, these works are summarized and tabulated based on the operating conditions, spectrum-selectivity, materi- als, and productivity. A discussion is finally presented concerning future development of photo-thermal catalytic reactions with spectrum-selectivity.

关键词： photo-thermal catalysis spectrtun-selectivity,solar fuel full-spectrum