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Effect of Crystallization Conditions on Polymorphic Diversity of Malic Acid RS-Racemate

Transactions of Tianjin University 2013年第2期19卷 86-91页

作者： Isakov A I Kotelnikova E N kryuchkova l yu lorenz H St.Petersburg State University St.Petersburg 199034Russia Max Planck Institute for Dynamics of Complex Technical Systems Magdeburg 39106Germany

Enantiomers （R （＋） and S（-））, RS-racemate mixture of enantiomers） of malic acid C4H605 have been （double compound） and （R ＋ S） -conglomerate （mechanical investigated by means of X-ray diffractometry and high tern- perature X-ray diffraction method. The RS-racemate was found to be able to form three polymorphic modifications, which we denominated as M1 （monoclinic, space group P21/c）, M2 （monoclinic, space group Cc）, and Tc （triclinic, space group P-l ）, the latter modification having been unknown before. Modification Tc was also described, and its X- ray diffraction characteristics, including interplanar spacings d, hkl indices, unit cell parameters, were defined. In addi- tion, X-ray diffraction characteristics for both reported earlier M1 and M2 monoclinic polymorphic modifications were measured with higher accuracy. The ability of RS-racemate to form one of the above three modifications （MI, M2, and Tc） or their mixtures containing various proportions and combinations of the components （M1 ＋ M2, M1 ＋ Tc, or M2 ＋ Tc） was found to depend on the type of crystallization medium （a melt, aqueous medium, ethanol or acetone solu- tion）, crystallization rate （from 2--3 minutes to 4 months）, and crystallization temperature. Heating S-enantiomer and M1 RS-racemate up to their respective melting points （100 ℃ and 124 ℃, correspondingly） only made them undergo thermal deformations, while heating （R ＋ S） -conglomerate in the temperature range of 96--110 ℃ resulted in its homogenization to form M2 RS-racemate, which, near the melting point （118 ℃）, namely, in the range of 112-116 ℃, was transformed into MI RS-racemate. Keywords： polvmorDhism; racemic, chiral

关键词： polymorphism racemic chiral

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Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni2P for lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 760-769页

作者： lin Peng yu Bai Hang li Meixiu Qu Zhenhua Wang Kening Sun Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing Key laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

lithium-sulfur （li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2P by concurrently introducing B-doped atoms and P vacancies in Ni2P （Vp-B-Ni2P）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni2P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides （liPSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni2P selectively promotes li2S dissolution and nucleation ***,the li-S batteries with Vp-B-Ni2P-separators present outstanding rate ability of 777 m A h g-1at 5 C and high areal capacity of 8.03 mA h cm-2under E/S of 5μl mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： lithium sulfur batteries

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low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu Cun liu Yiren yu Guoshu Gao yumeng Zhao Xiongfu Zhang Guodong liu Guohui Yang State Key laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology State Key laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 l highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： MFI zeolite ZSM-5 Nanosheets Scale-up synthesis Aromatic alkylation

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Dynamic heating and thermal destruction conditions of quartz particles in polydisperse plasma flow of RF-ICP torch system

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Plasma Science and Technology 2020年第11期22卷 114-126页

作者： l MIAO yu M GRISHIN Department of Thermophysics Moscow State Technical University N E BaumanMoscow 105005Russia

Numerical simulation of turbulent mixing process of polydisperse quartz particle(particle size distribution in the range of 0.1-0.4 mm)flow with Ar and Ar-H2 plasma generated by radio frequency inductively coupled plasma(RF-ICP)torch has been *** approximate two-stage approach has been proposed to calculate the spatial-temporal distributions of temperature and resulting thermal stress in quartz particles during dynamic heating in polydisperse plasma *** influence of working gas compositions,particle size distributions,injection angle and flow rate of carrier gas on the thermal destruction conditions of quartz particles has been determined under different particle feed *** is found that all the solid quartz particles(0.1-0.4 mm)could be thermal destructed without overheating in RF-ICP torch system,when the hydrogen volume fraction in working gases is more than 1.5%-2%and particle feed rate is in a certain *** values of the maximum and minimum feed rates have been determined under different hydrogen volume *** optimal particle injection angle and flow rate of carrier gas is found around 50°-60°and 160-220 slpm,under which the value of maximum equivalent thermal stress in quartz particles is highest.

关键词： RF-ICP torch dynamic heating thermal destruction hydrogen volume fraction optimal injection conditions

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Complex Cyber-Physical Networks： From Cybersecurity to Security Control

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Journal of Systems Science & Complexity 2017年第1期30卷 46-67页

作者： WEN Guanghui yu Wenwu yu Xinghuo lü Jinhu Department of Mathematics Southeast University Nanjing 210096 China. School of Engineering RMIT University Melbourne VIC 3001 Australia Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190 China

Complex cyber-physical network refers to a new generatio~ of complex networks whose normal functioning significantly relies on tight interactions between its physical and cyber compo- nents. Many modern critical infrastructures can be appropriately modelled as complex cyber-physical networks. Typical examples of such infrastructures are electrical power grids, WWW, public trans- portation systems, state financial networks, and the Interact. These critical facilities play important roles in ensuring the stability of society as well as the development of economy. Advances in informa- tion and communication technology open opportunities for malicious attackers to launch coordinated attacks on cyber-physical critical facilities in networked infrastructures from any Interact-accessible place. Cybersecurity of complex cyber-physical networks has emerged as a hot topic within this con- text. In practice, it is also very crucial to understand the interplay between the evolution of underlying network structures and the collective dynamics on these complex networks and consequently to design efficient security control strategies to protect the evolution of these networks. In this paper, cybersecu- rity of complex cyber-physical networks is first outlined and then some security enhancing techniques, with particular emphasis on safety communications, attack detection and fault-tolerant control, are suggested. Furthermore, a new class of efficient secure the achievement of desirable pinning synchronization control strategies are proposed for guaranteeing behaviors in complex cyber-physical networks against malicious attacks on nodes. The authors hope that this paper motivates to design enhanced security strategies for complex cyber-physical network systems, to realize resilient and secure critical infrastructures.

关键词： Communication topology complex cyber-physical network cybersecurity Internet ofThings secure control.

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Nanograting-Based Dynamic Structural Colors Using Heterogeneous Materials

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NANO-MICRO lETTERS 2025年第1期17卷 1-14页

作者： Wang, Jingang yu, Haibo Zheng, Jianchen Zhang, yuzhao Guo, Hongji Qiu, Ye Wang, Xiaoduo Yang, Yongliang liu, lianqing Chinese Acad Sci Shenyang Inst Automat State Key Lab Robot Shenyang 110016 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China

A 2.5-dimensional dynamic structural color based on nanogratings of heterogeneous materials was proposed by interweaving a pH-responsive hydrogel with IP-l *** nanogrid structures exhibit brilliant tuneable structural color, high sensitivity, and ultrafast recovery speeds in response to *** 4D printing-based grayscale design approach was proposed for the patterned encoding and array printing of dynamic structural colors, promoting their application in patterned printing, information encryption, and microfluidic chip sensing. Dynamic structural colors can change in response to different environmental stimuli. This ability remains effective even when the size of the species responsible for the structural color is reduced to a few micrometers, providing a promising sensing mechanism for solving microenvironmental sensing problems in micro-robotics and microfluidics. However, the lack of dynamic structural colors that can encode rapidly, easily integrate, and accurately reflect changes in physical quantities hinders their use in microscale sensing applications. Herein, we present a 2.5-dimensional dynamic structural color based on nanogratings of heterogeneous materials, which were obtained by interweaving a pH-responsive hydrogel with an IP-l photoresist. Transverse gratings printed with pH-responsive hydrogels elongated the period of longitudinal grating in the swollen state, resulting in pH-tuned structural colors at a 45 degrees incidence. Moreover, the patterned encoding and array printing of dynamic structural colors were achieved using grayscale stripe images to accurately encode the periods and heights of the nanogrid structures. Overall, dynamic structural color networks exhibit promising potential for applications in information encryption and in situ sensing for microfluidic chips.

关键词： Dynamic structural colors Four-dimensional printing pH-responsive Nanogrid Heterogeneous materials

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Preparation of Co/S co-doped carbon catalysts for excellent methylene blue degradation

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 169-181页

作者： Haixu li Haobo He Tiannan Jiang yunfei Du Zhichen Wu liang Xu Xinjie Wang Xiaoguang liu Wanhua yu Wendong Xue School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Beijing Jinyu Tongda Refractory Technologies Co. Ltd.Beijing 100085China

S and Co co-doped carbon catalysts were prepared via pyrolysis of MOF-71 and thiourea mixtures at 800℃at a mass ratio of MOF-71 to thiourea of 1:0.1 to effectively activate peroxymonosulfate(PMS)for methylene blue(MB)*** effects of two different mixing routes were identified on the MB degradation ***,the catalyst obtained by the alcohol solvent evaporation(MOF-AEP)mixing route could degrade 95.60%MB(50 mg/l)within 4 min(degradation rate:K=0.78 min^(-1)),which was faster than that derived from the direct grinding method(MOF-DGP,80.97%,K=0.39 min^(-1)).X-ray photoelectron spectroscopy revealed that the Co-S content of MOF-AEP(43.39at%)was less than that of MOF-DGP(54.73at%),and the proportion of C-S-C in MOF-AEP(13.56at%)was higher than that of MOF-DGP(10.67at%).Density functional theory calculations revealed that the adsorption energy of Co for PMS was -2.94 eV when sulfur was doped as C-S-C on the carbon skeleton,which was higher than that when sulfur was doped next to cobalt in the form of Co-S bond(-2.86 eV).Thus,the C-S-C sites might provide more contributions to activate PMS compared with ***,the degradation parameters,including pH and MOF-AEP dosage,were ***,radical quenching experiments and electron paramagnetic resonance(EPR)measurements revealed that ^(1)O_(2)might be the primary catalytic species,whereas·O~(2-)might be the secondary one in degrading MB.

关键词： advanced oxidation process alcohol solvent evaporation hydrogen bond S and Co co-doped carbon catalysts wastewater remediation

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Economic power dispatch in smart grids: a framework for distributed optimization and consensus dynamics

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Science China(Information Sciences) 2018年第1期61卷 233-248页

作者： Wenwu yu Chaojie lI Xinghuo yu Guanghui WEN Jinhu l School of Mathematics Southeast University NAAM Research Group Department of Mathematics Faculty of ScienceKing Abdulaziz University School of Engineering RMIT University Academy of Mathematics and Systems Science Chinese Academy of Sciences University of Chinese Academy of Sciences

By using the distributed consensus theory in multi-agent systems, the strategy of economic power dispatch is studied in a smart grid, where many generation units work cooperatively to achieve an optimal solution in a local area. The relationship between the distributed optimization solution and consensus in multi-agent systems is first revealed in this paper, which can serve as a general framework for future studies of this topic. First, without the constraints of capacity limitations, it is found that the total cost for all the generators in a smart grid can achieve the minimal value if the consensus can be reached for the incremental cost of all the generation units and the balance between the supply and demand of powers is kept. Then, by designing a distributed consensus control protocol in multi-agent systems with appropriate initial conditions,incremental cost consensus can be realized and the balance for the powers can also be satisfied. Furthermore,the difficult problem for distributed optimization of the total cost function with bounded capacity limitations is also discussed. A reformulated barrier function is proposed to simplify the analysis, under which the total cost can reach the minimal value if consensus can be achieved for the modified incremental cost with some appropriate initial values. Thus, the distributed optimization problems for the cost function of all generation units with and without bounded capacity limitations can both be solved by using the idea of consensus in multi-agent systems, whose theoretical analysis is still lacking nowadays. Finally, some simulation examples are given to verify the effectiveness of the results in this paper.

关键词： power dispatch strategy consensus incremental cost capacity limitations distributed protocol multi-agent systems

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Effect of relative humidity on the desulfurization performance of calcium-based desulfurizer

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Journal of Environmental Sciences 2024年第4期138卷 179-188页

作者： Juan lǖ yu Fu Haiyan yu HuanWang Zhe Wang Haiyan Chen School of Environment and Resource Southwest University of Science and TechnologyMianyang 621010China Guangyuan Emergency Management bureau Guangyuan 628000China

low desulfurization efficiency impedes the wide application of dry desulfurization technology,which is a low-cost and simple process,and one significant solution is the development and manufacture of high-performance *** this study,firstly,a steam jet mill was used to digest quicklime;then,we utilized numerical simulation to study the flow field distribution and analyze the driving factors of quicklime digestion;and lastly,the desulfurization performance of the desulfurizer was evaluated under different relative *** results show that the desulfurizer prepared via the steam jet mill had better apparent activity than traditional ***,the entire jet flow field of the steam jet mill is in a supersonic and highly turbulent flow state,with high crushing intensity and good particle acceleration *** contact with the nascent surface maximizes the formation of slaked *** experiments demonstrated that the operating time with 100%desulfurization efficiency and the“break-through”time for the desulfurizer prepared via the steam jet mill is longer than that of traditional desulfurizers,and has significant advantages,especially at low flue gas relative *** with traditional desulfurizers,the desulfurizer prepared via steam jet mill expands the range of acceptable flue gas temperature,and the failure temperature is 1.625 times that of traditional *** work breaks through the technical bottleneck of low dry desulfurization efficiency,which is an important step in pushing forward the application of dry desulfurization.

关键词： Dry desulfurization Relative humidity Desulfurization efficiency High-efficiency desulfurizer Quicklime digestion

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Information geography: A new fulcrum of geographic ternary world

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Science China Earth Sciences 2022年第2期65卷 383-386页

作者： Guonian lÜ linwang yuAN Zhaoyuan yu Key laboratory of Virtual Geographic Environment School of GeographyNanjing Normal UniversityMinistry of EducationNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China State Key laboratory Cultivation Base of Geographical Environment Evolution(Jiangsu Province) Nanjing 210023China

The development trend of ternary space requires the construction of the information space for information mapping,transmission and transformation of geographic elements and social-human elements. Relevant researches of information geography from the perspective of Geographic Information Science and human geography are reviewed in this paper, then the concept interpretation of information geography from the perspective of ternary space is proposed. It is presented in this paper that information geography can be constructed with a framework using seven geographic elements as the basic expressing dimensions and seven social-human elements as the basic aggregating core. Information geography analyzes spatio-temporal distribution, structural characteristics, evolution process and interactions of various elements in the information space. And it eventually realizes the actual description, multi-scenario simulation, multi-objective decision-making and multi-channel control of the physical world and the social-human world.

关键词： Information geography Ternary space Seven geographic elements Seven social-human elements

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