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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

Power-Aware Data Management Based on Hybrid RAM-NVM Memory for Smart Bracelet

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Journal of Electronic Science and Technology 2017年第4期15卷 385-390页

作者： Jin-Yu Zhan Jun-Huan Yang Wei jiang yi-xin Li yi-Ming Zhang School of Information and Software Engineering University of Electronic Science and Technology of China Chengdu 610054 China State Key Lab of Mathematical Engineering and Advanced Computing Wuxi 214000China

Wearable devices become popular because they can help people observe health *** battery life is the critical problem for wearable devices. The non-volatile memory(NVM) attracts attention in recent years because of its fast reading and writing speed, high density, persistence, and especially low idle power. With its low idle power consumption,NVM can be applied in wearable devices to prolong the battery lifetime such as smart bracelet. However, NVM has higher write power consumption than dynamic random access memory(DRAM). In this paper, we assume to use hybrid random access memory(RAM)and NVM architecture for the smart bracelet *** paper presents a data management algorithm named bracelet power-aware data management(BPADM) based on the architecture. The BPADM can estimate the power consumption according to the memory access, such as sampling rate of data, and then determine the data should be stored in NVM or DRAM in order to satisfy low power. The experimental results show BPADM can reduce power consumption effectively for bracelet in normal and sleeping modes.

关键词： Hybrid memory non-volatile memory(NVM) power-aware smart bracelet

Chemo-enzymatic Synthesis of Z-Asp-Val-Tyr-NH_2——A Precursor Tripeptide of Thymopentin

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Chemical Research in Chinese Universities 2010年第6期26卷 942-947页

作者： GUO yi ZHANG Yong-xia jiang xin ZHANG Xue-zhong WU yi XU Li Key Laboratory for Molecular Enzymology and Engineering Ministry of Education Jilin University Changchun 130012 P. R. China College of Pharmacy Jilin University Changchun 130021 P. R. China

Z-Asp-Val-Tyr-NH2,a precursor tripeptide of thymopentin（TP-5）,was successfully synthesized by a combination of chemical and enzyme ***,the precursor dipeptide Val-Tyr-NH2 was synthesized by a novel chemical method in four steps including the preparation of NCA-Val,the esterification of L-tyrosine and the ammonolysis of L-tyrosine ethyl ester,and the formation of Val-Tyr-NH2 from NCA-Val and ***,a thermolysin,thermoase PC 10F was used to catalyze the formation of Z-Asp-Val-Tyr-NH2 in an aqueous/organic solvent diphase system with Z-Asp-OH and Val-Ty-NH2 as the substrates under thermodynamic *** optimum conditions were pH=6.5,40 ℃,thermoase 100 mg,in 2-（N-morpholino） ethanesulfonic acid MES/NaOH（containing 5 mmol/L CaCl2） of n-butanol system（15/85,volume ratio） for 20 h in a maximum yield of 27.02%.

关键词： Thymopentin Peptide synthesis Thermoase Organic solvent

Statistical analysis on the validity of the cold plasma approximation for chorus waves based on Van Allen Probe observations and their effects on radiation belt electrons

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Earth and Planetary Physics 2025年第1期9卷 159-170页

作者： AoJun Ren jiang Yu Jing Wang ZuZheng Chen XiaoMan Liu Planetary Environmental and Astrobiological Research Laboratory(PEARL) School of Atmospheric SciencesSun Yat-sen UniversityZhuhai Guangdong 519000China

Theoretical analysis has demonstrated that the dispersion relation of chorus waves plays an essential role in the resonant interaction and energy transformation between the waves and magnetospheric *** quantitative analyses often simplified the chorus dispersion relation by using the cold plasma ***,the applicability of the cold plasma assumption is doubtful,especially during geomagnetic *** here present a systematic statistical analysis on the validity of the cold plasma dispersion relation of chorus waves based on observations from the Van Allen Probes over the period from 2012 to *** statistical results show that the observed magnetic field intensities deviate substantially from those calculated from the cold plasma dispersion relation and that they become more pronounced with an increase in geomagnetic activity or a decrease in background plasma *** region with large deviations is mainly concentrated in the nightside and expands in both the radial and azimuthal directions as the geomagnetic activity increases or the background plasma density *** addition,the bounce-averaged electron scattering rates are computed by using the observed and cold plasma dispersion relation of chorus *** with usage of the cold plasma dispersion relation,usage of the observed dispersion relation considerably lowers the minimum resonant energy of electrons and lowers the scattering rates of electrons above tens of kiloelectronvolts but enhances those ***,these differences are more pronounced with the enhancement of geomagnetic activity or the decrease in background plasma density.

关键词： chorus waves cold plasma approximation dispersion relations scattering rates

Dynamic analysis of the tethered satellite system considering uncertain but bounded parameters

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Defence Technology（防务技术） 2024年第12期42卷 116-124页

作者： xin jiang Zhengfeng Bai School of Astronautics Harbin Institute of TechnologyHarbin150001China Department of Mechanical Engineering Harbin Institute of TechnologyWeihai264209China

Dynamic analysis of the tethered satellite system(TSS)can provide a fundamental guideline to the evaluation of performance and robust design of the system *** inherited with the parameters would induce unexpected variation of the response and deteriorate the reliability of the *** this work,the effect of uncertain mass of the satellites on the deployment and retrieval dynamics of the TSS is *** the interval mode is employed to take the variation of mass of satellite into account in the processes of deployment and ***,the Chebyshev interval method is used to obtain the lower and upper response bounds of the *** achieve a smooth and reliable implementation of deployment and retrieval,the nonlinear programming based on the Gauss pseudospectral method is adopted to obtain optimal trajectory of tether *** results show that the uncertainties of mass of the satellites have a distinct influence on the response of tether tension in the processes of deployment and retrieval.

关键词： Dynamic analysis Interval uncertainty Tethered satellite Deployment and retrieval

RRS-PBC: a molecular approach for periodic systems

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Science China Chemistry 2014年第10期57卷 1399-1404页

作者： ZHANG Igor ying jiang Jun GAO Bin XU xin LUO yi Laboratory for Computational Physical Science Ministry of Education Shanghai Key Laboratory Mol Catalysis & Innovative Materals Collaborative Innovation Center of Chemistry for Energy Materials Department of Chemistry Fudan University Department of Theoretical Chemistry School of Biotechnology Royal Institute of Technology KTH Sweden Heifei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of China

Technically, when dealing with a perfect crystal, methods （PBC） in conjunction with plane-wave basis sets are widely in k-（reciprocal） space that impose periodic boundary conditions used. Chemists, however, tend to think of a solid as a giant mole- cule, which offers a molecular way to describe a solid by using a finite cluster model （FCM）. However, FCM may fail to sim- ulate a perfect crystal due to its inevitable boundary effects. We propose an RRS-PBC method that extracts the k-space infor- mation of a perfect crystalline solid out of a reduced real space （RRS） of an FCM. We show that the inevitable boundary effects in an FCM are eliminated naturally to achieve converged high-quality band structures.

关键词： periodic boundary condition finite cluster model boundary effects band structures

Effect of chemical reactivity on the detonation initiation in shock accelerated flow in a confined space

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Acta Mechanica Sinica 2013年第1期29卷 54-61页

作者： Yue-Jin Zhu Gang Dong yi-xin Liu Bao-Chun Fan Hua jiang State Key Laboratory of Transient Physics Nanjing University of Science and Technology State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology

The interactions of a spherical flame with an incident shock wave and its reflected shock wave in a confined space were investigated using the three-dimensional reactive Navier-Stokes equations, with emphasis placed on the effect of chemical reactivity of mixture on the flame distortion and detonation initiation after the passage of the reflected shock wave. It is shown that the spatio-temporal characteristics of detonation initiation depend highly on the chemi- cal reactivity of the mixture. When the chemical reactivity enhances, the flame can be severely distorted to form a reactive shock bifurcation structure with detonations initiating at different three-dimensional spatial locations. Moreover, the detonation initiation would occur earlier in a mixture of more enhanced reactivity. The results reveal that the detona- tions arise from hot spots in the unburned region which are initiated by the shock-detonation-transition mechanism.

关键词： Chemical reactivity Reactive shock bifurcation structure ~ Detonation initiation Hot spot Shock wave

Automated regression unit test generation for program merges

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Science China(Information Sciences) 2022年第9期65卷 297-298页

作者： Tao JI Liqian CHEN Xiaoguang MAO xin yi Jiahong jiang College of Computer National University of Defense Technology Beijing Institute of Tracking and Telecommunication Technology

Dear editor,Merging of various branches of software with the current branch is common in collaborative software *** decades of hard work on detecting merge conflicts,various tools have been proposed [1] for assisting software developers in detecting and resolving conflicts. However,software developers are still deeply relying on textual merge tools to handle complicated merge tasks [2]. They may not be able to detect latent semantic merge conflicts, which reduces the software quality.

关键词： Software testing

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Topological representations of crystalline compounds for the machine-learning prediction of materials properties

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npj Computational Materials 2021年第1期7卷 240-247页

作者： yi jiang Dong Chen xin Chen Tangyi Li Guo-Wei Wei Feng Pan School of Advanced Materials Peking UniversityShenzhen Graduate SchoolShenzhenPR China Department of Mathematics Michigan State UniversityEast LansingMIUSA

Accurate theoretical predictions of desired properties of materials play an important role in materials research and *** learning(ML)can accelerate the materials design by building a model from input *** complex datasets,such as those of crystalline compounds,a vital issue is how to construct low-dimensional representations for input crystal structures with chemical *** this work,we introduce an algebraic topology-based method,called atom-specific persistent homology(ASPH),as a unique representation of crystal *** ASPH can capture both pairwise and many-body interactions and reveal the topology-property relationship of a group of atoms at various *** with composition-based attributes,ASPH-based ML model provides a highly accurate prediction of the formation energy calculated by density functional theory(DFT).After training with more than 30,000 different structure types and compositions,our model achieves a mean absolute error of 61 meV/atom in cross-validation,which outperforms previous work such as Voronoi tessellations and Coulomb matrix method using the same ML algorithm and *** results indicate that the proposed topology-based method provides a powerful computational tool for predicting materials properties compared to previous works.

关键词： crystalline topology crystal