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Chinese Journal of Chemical Engineering 2022年第7期35卷 31-38页

作者： Jie wei weiwei Yang shuai Jia Jie wei Ziqiang Shao Beijing Engineering Research Center of Cellulose and Its Derivatives School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China

Cellulose and its derivatives are natural materials with high carbon contents, but it is challenging to convert their carbon into high value-added carbonaceous materials(e.g., graphene). Here, an approach to convert the carbon in cellulose into N, P co-doped porous graphene(LIG) materials via laser induction is proposed. Cellulose nanofibrils(CNFs), a cellulose derivative with high dispersion uniformity and abundant surface hydroxyl groups, were easily formed on a bulk substrate(thickness ≥5 mm) containing ammonium polyphosphate(APP). Then, a 10.6 μm CO2 laser was used to scribe for 1–5 passes on the CNFs/APP substrate under an ambient environment to produce N, P co-doped porous LIG. Upon increasing the number of laser scribing passes, the IG/IDof LIG first increased and then decreased, reaching a maximum of 1.68 at 4 passes. The good pore structure and low resistance also showed that 4 laser passes were ideal. Besides, the N, P co-doped LIG also showed excellent electrochemical performance, with a specific capacitance of 221.4 FF·g^(-1) and capacitance retention of 89.9%. This method exploits the advantages of nanocellulose and overcomes the difficulties associated with directly compounding cellulosic materials, providing a method for the further development of biomass nanomaterials.

关键词： Cellulose nanofibrils Laser induction Porous graphene Multiple lasing Supercapacitor

基于纳秒LIBS的氢气/空气火焰混合分数测量研究

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光谱学与光谱分析 2025年第1期45卷 24-29页

作者：刘子晗刘艳韩磊单沅鲁政高强李帅瑶李博天津大学内燃机燃烧学国家重点实验室天津300072 中国科学院工程热物理研究所北京100190

在双碳政策和化石能源短缺的背景下,氢能作为高效环保的清洁能源,受到广大研究人员的关注。氢气/空气混合燃烧作为推动氢能规模化应用的重要途径,其燃烧机理和关键参数的测量技术成为目前研究的热点。燃空当量比是表征燃烧过程中燃料与... 详细信息

在双碳政策和化石能源短缺的背景下,氢能作为高效环保的清洁能源,受到广大研究人员的关注。氢气/空气混合燃烧作为推动氢能规模化应用的重要途径,其燃烧机理和关键参数的测量技术成为目前研究的热点。燃空当量比是表征燃烧过程中燃料与氧化剂混合程度的重要参数,直接影响燃烧的开始、自持以及燃烧化学反应的活跃程度。因此,对燃烧过程中的局部当量比实时在线监测,对于改善燃烧效率、控制燃烧过程具有重要意义。目前,可以实时测量氢气/空气火焰当量比的方法相对较少,激光光谱技术作为一种非侵入式的测量方法,不仅具有实时在线测量的能力,还具有快速、原位、远程分析、多元素同时在线监测等特点,在燃烧测量领域具有重要的应用潜力。采用纳秒激光诱导击穿光谱技术对氢气和空气燃烧场的燃空当量比进行测量研究。氢气和空气在管内混合后,由射流口喷出形成射流燃烧火焰场。激光通过透镜聚焦到射流燃烧场中击穿并产生等离子体,其等离子体的发射光谱由光谱仪采集,实验发现光谱中H 656 nm和O 777 nm具有很强的发射强度,且光谱强度随着当量比的变化,呈现规律性变化趋势。因此,采用H 656 nm和O 777 nm的光谱分别标示氢气和空气,并将其比值作为燃空当量比的测量参量。实验在氢气空气混合均匀的低速流场中测量了不同当量比下H 656 nm与O 777 nm的光谱强度比值,并与当量比建立标定曲线,实验发现该标定曲线对燃烧场和非燃烧场同样适用。基于标定曲线,我们研究了存在外界掺混情况下,射流燃烧场的局部燃空当量比情况。在当量比1.0,流场速度为20 m·s^(-1)的射流燃烧场中,测量了射流中心位置不同高度的燃空当量比变化情况,并在相同工况下进行了数值模拟。模拟结果与实验测量吻合较好,验证了纳秒激光诱导击穿光谱技术测量氢气/空气混合气的燃空当量比的可行性。该方法可为氢气燃烧基础研究及数值模拟提供技术支持。

关键词：激光诱导击穿光谱氢能当量比模拟

Practical Model of Sea Ice Thickness of Bohai Sea Based on MODIS Data

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Chinese Geographical Science 2018年第5期28卷 863-872页

作者： YUAN shuai liu Chengyu liu Xueqin Marine Environmental Monitoring Center State Oceanic Administration Key Laboratory of Spatial Active Opto-Electronic Techniques Shanghai Institute of Technical PhysicsChinese Academy of Sciences

Sea ice thickness is one of the most important input parameters in the studies on sea ice disaster prevention and mitigation. It is also the most important content in remote sensing monitoring of sea ice. In this study, a practical model of sea ice thickness(PMSIT) was proposed based on the Moderate Resolution Imaging Spectroradiometer(MODIS) data. In the proposed model, the MODIS data of the first band were used to estimate sea ice thickness and the difference between the second-band reflectance and the fifth-band reflectance in the MODIS data was calculated to obtain the difference attenuation index(DAI) of each pixel. The obtained DAI was used to estimate the integrated attenuation coefficient of the first band of the MODIS at the pixel level. Then the model was used to estimate sea ice thickness in the Bohai Sea with the MODIS data and then validated with the actual sea ice survey data. The validation results showed that the proposed model and corresponding parameterization scheme could largely avoid the estimation error of sea ice thickness caused by the spatial and temporal heterogeneity of sea ice extinction and allowed the error of 18.7% compared with the measured sea ice thickness.

关键词： sea ice thickness Moderate Resolution Imaging Spectroradiometer(MODIS) practical model Bohai Sea

A comparative study of network robustness measures

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Frontiers of Computer Science 2017年第4期11卷 568-584页

作者： Jing liu Mingxing ZHOU shuai WANG Penghui liu Key Laboratory of intelligent Perception and Image Understanding of Ministry of Education Xidian University Xi'an 710071 China

The robustness is an important functionality of networks because it manifests the ability of networks to resist failures or attacks. Many robustness measures have been proposed from different aspects, which provide us various ways to evaluate the network robustness. However, whether these measures can properly evaluate the network robustness and which aspects of network robustness these measures can evaluate are still open questions. Therefore, in this paper, a thorough introduction over attacks and robustness measures is first given, and then nine widely used robustness mea- sures are comparatively studied. To validate whether a robustness measure can evaluate the network robustness properly, the sensitivity of robustness measures is first studied on both initial and optimized networks. Then, the performance of robustness measures in guiding the optimization process is studied, where both the optimization process and the ob- tained optimized networks are studied. The experimental re- suits show that, first, the robustness measures are more sen- sitive to the changes in initial networks than to those in op- timized networks; second, an optimized network may not be useful in practical situations because some useful function- alities, such as the shortest path length and communication efficiency, are sacrificed too much to improve the robustness; third, the robustness of networks in terms of closely corre- lated robustness measures can often be improved together. These results indicate that it is not wise to just apply the opti- mized networks obtained by optimizing over one certain robustness measure into practical situations. Practical requirements should be considered, and optimizing over two or more suitable robustness measures simultaneously is also a promising way.

关键词： scale-free network malicious attack robustnessmeasure hill climbing algorithm

Autonomous Vessel Scheduling

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Journal of the Operations Research Society of China 2020年第3期8卷 391-414页

作者： wei Zhang shuai-An Wang Department of Logistics and Maritime Studies Hong Kong Polytechnic UniversityHong KongChina The Hong Kong Polytechnic University Shenzhen Research Institute Shenzhen 518057GuangdongChina

This study deals with an autonomous vessel scheduling problem when collaboration exists between port operators and an autonomous vessel company.A mixedinteger nonlinear programming model is developed,including decisions in assigning autonomous vessels to berths at each port and the optimal arrival time of each vessel at each port in an entire autonomous shipping *** study aims to minimize the total cost of fuel consumption and the delay penalty of an autonomous vessel *** nonlinear programming model is linearized and further solved using off-the-shelf *** experiments are conducted to test the effectiveness of the model and to draw insights for commercializing autonomous *** show that a company may speed up an autonomous vessel with short-distance voyage once fuel price decreases to gain additional benefits.

关键词： Autonomous vessel Autonomous ship Ship scheduling Berth allocation

Knowledge Compilation Methods Based on the Clausal Relevance and Extension Rule

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Chinese Journal of Electronics 2018年第5期27卷 1037-1042页

作者： NIU Dangdang liu Lei LYU shuai College of Computer Science and Technology Jilin University Key Laboratory of Symbolic Computation and Knowledge Engineering (Jilin University) Ministry of Education

We introduce the concepts of Relevancematrix(RM) and Relevance-set(RS). And we construct the association between RM and the Knowledge compilation(KC) methods based on Extension rule(ER). Based on the basic parameters of RS and the relationship between RM and the KC methods based on ER, we design two efficient heuristics, called M2S(maximum sum of elements in RS and sum of literals in RS) and MNE(minimum number of maximum terms not extended by RS). Both of above heuristics intend to find the minimum set of maximum terms which cannot be extended by RS. Furthermore,we apply M2S and MNE on KCER. M2S KCER(KCER with M2S) and MNE KCER(KCER with MNE) are designed and implemented based on M2S and MNE, respectively. Experimentally, for the SAT instances with random lengths of clauses, M2S KCER and MNE KCER can improve the efficiency and quality of KCER sharply, and they are two best KC algorithms of EPCCL(each pair contains complementary literal) theory in all KC algorithms based on KCER.

关键词： Extension rule Knowledge compilation Clausal relevance Heuristic strategy

Observer-based distributed consensus for nonlinear multi-agent systems with limited data rate

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Science China(Information Sciences) 2022年第9期65卷 191-205页

作者： Jing ZHANG shuai liu Xianfu ZHANG School of Control Science and Engineering Shandong University

In this paper, we investigate the observer-based distributed consensus problem for nonlinear multi-agent systems with a limited data rate. We assume that each agent displays strict-feedback nonlinear dynamics. An observer is constructed to estimate the system states as they cannot be directly *** quantizers and logarithmic quantizers are considered in communication channels among agents and observer-based distributed control protocols are proposed for each agent. For the uniform quantizer, theδ-asymptotic distributed consensus, with δ being the resolution of the quantizer, can be achieved under the proposed control protocol, i.e., the consensus errors tend to zero as δ approaches zero. For the logarithmic quantizer, the asymptotic consensus can be achieved. The simulation results reveal the conclusion.

关键词： nonlinear multi-agent systems uniform quantizer logarithmic quantizer dynamic gain δ-asymptotic distributed consensus

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3D coarse-grained DPM simulation of the MIP reaction-regeneration loop

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Particuology 2024年第6期89卷 57-66页

作者： Yanhao Ye shuai Zhang Ji Xu wei Ge State Key Laboratory of Mesoscience and Engineering(formerly State Key Laboratory of Multiphase Complex Systems) Institute of Process EngineeringChinese Academy of SciencesBeijing100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China

The reactor-regenerator loop is the core facility of the maximizing iso-paraffin(MIP)*** the discrete particle method(DPM)simulation can provide detailed information at the particle scale,it has been unable to simulate such a complex loop system due to limitations of coarse-grained(CG)models,computing software,and *** this study,a newly proposed soft-shell CG-DPM model with a CG ratio of up to 800 is used to simulate a 3.5 Mt/a industrial-scale MIP reactor-regenerator *** solid fraction distribution obtained is found to agree well with in-situ *** properties including the distribution of solid fraction,gas and solid velocity,standard derivation of solid fraction with time,temporal distribution of the flow field,and particle residence time distribution are measured in the simulation,which are meaningful to better design and operate such systems in the future.

关键词： Discrete particle method Coarse-grain Maximizing iso-paraffins Full-loop Reaction-regeneration system

Effect of inertial particles with different specific heat capacities on heat transfer in particle-laden turbulent flow

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Applied Mathematics and Mechanics(English Edition) 2017年第8期38卷 1149-1158页

作者： Caixi liu shuai TANG Yuhong DONG Shanghai Institute of Applied Mathematics and Mechanics Shanghai UniversityShanghai 200072China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai UniversityShanghai 200072China

The effect of inertial particles with different specific heat on heat transfer in particle-laden turbulent channel flows is studied using the direct numerical simulation（DNS） and the Lagrangian particle tracking method. The simulation uses a two-way coupling model to consider the momentum and thermal interactions between the particles and turbulence. The study shows that the temperature fields display differences between the particle-laden flow with different specific heat particles and the particle-free flow,indicating that the particle specific heat is an important factor that affects the heat transfer process in a particle-laden flow. It is found that the heat transfer capacity of the particle-laden flow gradually increases with the increase of the particle specific heat. This is due to the positive contribution of the particle increase to the heat transfer. In addition,the Nusselt number of a particle-laden flow is compared with that of a particle-free *** is found that particles with a large specific heat strengthen heat transfer of turbulent flow, while those with small specific heat weaken heat transfer of turbulent flow.

关键词： turbulent laden turbulence inertial Reynolds Lagrangian momentum dissipation fluctuation incompressible

Efficacy evaluation and survival analysis of the combination of oxaliplatin plus Teysuno (SOX) with immune checkpoint inhibitors in the conversion therapy of locally advanced gastric cancer

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Oncology and Translational Medicine 2024年第4期10卷 190-197页

作者： shuai liu Kai Zhang Xiaoqing Zhang wei Luan Inner Mongolia Medical University Graduate School Urumchi 010000China The Inner Mongolia autonomous region people's hospital and oncology Urumchi 010000China

Background:The efficacy of combining immune checkpoint inhibitors(ICIs)with chemotherapy in neoadjuvant therapy for locally advanced gastric cancer has been ***,limited research exists on its effectiveness in conversion therapy,and its superiority over standalone chemotherapy remains to be *** study aims to investigate the efficacy and survival outcomes of patients treated with ICIs in combination with conversion therapy for locally advanced gastric ***:Retrospective data from patients with locally advanced gastric cancer treated with either oxaliplatin+S-1(SOX)alone or in combination with ICIs in conversion therapywere *** andpathological characteristics,disease-free survival,andefficacy assessments in nonoperable patients were compared between the 2 treatment *** was further evaluated through dynamic changes in serum markers,and patients’quality of life was assessed using the QLQ-STO22(Gastric Cancer–Specific Quality of Life Questionnaire)quality-of-life measurement ***:A total of 140 patients underwent conversion therapy:80 in the SOX alone group and 60 in the SOX combined with the ICIs *** were no significant differences in baseline characteristics between the 2 *** with the SOX alone group,the SOX combined with ICIs group exhibited a higher conversion rate(83.3%vs 75%,P=0.23),R0 resection rate(90.0%vs 83.3%,P=0.31),pathological complete response(pCR)rate(18%vs 5%,P=0.02),median disease-free survival(21.4 vs 16.9 months,P=0.007),the objective response rate in nonoperable patients(60%vs 40%,P=0.301),and median progression-free survival time(7.9 vs 5.7 months,P=0.009).The QLQ-STO22 quality-of-life assessment revealed statistically significant improvements in pain,swallowing difficulties,and dietary restrictions in the combination therapy group compared with those in the monotherapy *** enhanced efficacy of immune combination with SOX is evident,as demonstrated by the

关键词： Conversion therapy Locally advanced gastric cancer Immune checkpoint inhibitors Gastrectomy Efficacy evaluation Survival analysis Quality-of-life measurement