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Chinese Journal of Chemical Engineering 2024年第4期68卷 156-164页

作者： Kexin Zhang wenmin Zhang Heng An Zhe Huang yanzhen wen Xiangyu Jiao Yongqiang wen College of Chemical Engineering and Technology Taiyuan University of Science and TechnologyTaiyuan 030024China Beijing Key Laboratory for Bioengineering and Sensing Technology Daxing Research InstituteSchool of Chemistry&Biological EngineeringUniversity of Science&Technology BeijingBeijing 100083China

Delayed and nonhealing of diabetic wounds imposes substantial economic burdens and physical pain on patients.Mesenchymal stem cells(MSCs)promote diabetic wound healing.Particularly when MSCs aggregate into multicellular spheroids,their therapeutic effect is enhanced.However,traditional culture platforms are inadequate for the efficient preparation and delivery of MSC spheroids,resulting in inefficiencies and inconveniences in MSC spheroid therapy.In this study,a three-dimensional porous nanofibrous dressing(NFD)is prepared using a combination of electrospinning and homogeneous freeze-drying.Using thermal crosslinking,the NFD not only achieves satisfactory elasticity but also maintains notable cytocompatibility.Through the design of its structure and chemical composition,the NFD allows MSCs to spontaneously form MSC spheroids with controllable sizes,serving as MSC spheroid delivery systems for diabetic wound sites.Most importantly,MSC spheroids cultured on the NFD exhibit improved secretion of vascular endothelial growth factor,basic fibroblast growth factor,and hepatocyte growth factor,thereby accelerating diabetic wound healing.The NFD provides a competitive strategy for MSC spheroid formation and delivery to promote diabetic wound healing.

关键词： Electrospinning Homogenization Biomedical engineering Nanomaterials Stem cell spheroids Diabetic wound healing

Distributed Optimal Variational GNE Seeking in Merely Monotone Games

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1621-1630页

作者： Wangli He yanzhen Wang IEEE the Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

In this paper, the optimal variational generalized Nash equilibrium(v-GNE) seeking problem in merely monotone games with linearly coupled cost functions is investigated, in which the feasible strategy domain of each agent is coupled through an affine constraint. A distributed algorithm based on the hybrid steepest descent method is first proposed to seek the optimal v-GNE. Then, an accelerated algorithm with relaxation is proposed and analyzed, which has the potential to further improve the convergence speed to the optimal v-GNE. Some sufficient conditions in both algorithms are obtained to ensure the global convergence towards the optimal v-GNE. To illustrate the performance of the algorithms, numerical simulation is conducted based on a networked Nash-Cournot game with bounded market capacities.

关键词： Distributed algorithms equilibria selection generalized Nash equilibrium(GNE) merely monotone games

Physiological and psychological responses to tended plant communities with varying color characteristics

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Journal of Forestry Research 2024年第1期35卷 183-201页

作者： Siyuan Zheng yanzhen Zhou Haiyan Qu School of Architecture and Urban Planning Shenyang Jianzhu UniversityShenyang 110168People’s Republic of China

Exposure to plants has been reported to promote health and reduce stress,and plant color has direct impacts on physical and mental health.We used images of common types of tended plant communities in Shenyang,China,with combinations of yellow,green,and red foliage,as experimental stimuli.A total of 27 images were used as visual stimuli.We used electroencephalography to measureαwave activity(8-13 Hz)in 40 subjects while they viewed visual stimuli.These data were combined with subjective questionnaire data to analyze the relaxing effect of images of tended plant communities with different color types and proportions on people.The results revealed that,although there were slight differences between the electroencephalography and psychological findings,women were significantly more relaxed than men after viewing the images.Physiological and psychological responses varied with the types and proportions of colors in the tended plant communities:those of foliage with combinations of two or three colors induced stronger responses than images with a single color.Specifically,(1)for one-color plant communities,green or yellow plant communities induced a stronger relaxation effect than red plant communities;(2)for two-color plant communities,the optimal color proportion was 55%+45%,and the green+yellow and green+red color combinations induced a stronger relaxation effect;(3)for three-color plant communities,the relaxation effect was strongest when the color proportion was 55%green+25%yellow+20%red.These data would provide a plant color matching in future plant landscape design,which may be helpful for creating healthy and relaxing environments.

关键词： Plant community Color type Color ratio Electroencephalography Subjective questionnaire

Laboratory and field evaluation of a low-cost optical particle sizer

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Journal of Environmental Sciences 2024年第8期142卷 215-225页

作者： Mingzhen Tang Yicheng Shen yanzhen Ge Jian Gao Chong Wang Liqing Wu Shuchun Si State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Jinan Grid-Based Supervision Center of Ecological and Environmental Protection Jinan 250100China Tai’an Ecological Environment Protection Control Center Tai’an 271000China School of Physics Shandong UniversityJinan 250013China

Low-cost sensors are widely used to collect high-spatial-resolution particulate matter data that traditional reference monitoring devices cannot.In addition to the mass concentration,the number concentration and size distribution are also fundamental in determining the origin and hazard level of particulate pollution.Therefore,low-cost optical sensors have been improved to establish optical particle sizers(OPSs).In this study,a low-cost OPS,the Nova SDS029,is introduced,and it is evaluated in comparison to two reference instruments—the GRIMM 11-D and the TSI 3330.We first tested the sizing accuracy using polystyrene latex spheres.Then,we assessed the mass and number size distribution accuracy in three application scenarios:indoor smoking,ambient air quality,and mobile monitoring.The evaluations suggest that the low-cost SDS029 rivals research-grade optical sizers in many aspects.For example,(1)the particle diameters obtained with the SDS029 are close to the reference instruments(usually<10%)in the 0.3-5μm range;(2)the number of particles and mass concentration are highly correlated(r≥0.99)with the values obtained with the reference instruments;and(3)the SDS029 slightly underestimates the number concentration,but the derived PM_(2.5)values are closer to monitoring station than the reference instruments.The successful application of the SDS029 in multiple scenarios suggests that a plausible particle size distribution can be obtained in an easy and cost-efficient way.We believe that low-cost OPSs will increasingly be used to map the sources and risk levels of particles at the city scale.

关键词： Optical particle sizer Particle size distribution Low-cost sensor Evaluation Field application

气凝胶填充金属蜂窝夹层结构隔热性能试验与模拟

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中国机械工程 2023年第5期34卷 556-562页

作者：文彦臻邓云华贾震沈阳航空航天大学航空宇航学院沈阳110136 中国航空制造技术研究院航空焊接与连接技术航空科技重点实验室北京100024

在1300℃温度和30 min保温时间的条件下,使用Nb基钎料对铌合金进行钎焊来成形铌合金蜂窝。对铌合金蜂窝与气凝胶填充铌合金蜂窝进行加热试验,测定了热面与冷面的瞬态温度。在与实际试验条件基本保持一致的情况下,建立了金属蜂窝与气凝... 详细信息

在1300℃温度和30 min保温时间的条件下,使用Nb基钎料对铌合金进行钎焊来成形铌合金蜂窝。对铌合金蜂窝与气凝胶填充铌合金蜂窝进行加热试验,测定了热面与冷面的瞬态温度。在与实际试验条件基本保持一致的情况下,建立了金属蜂窝与气凝胶填充金属蜂窝的有限元模型,并对不同几何参数的蜂窝进行传热模拟,分析了蜂窝芯格壁厚、芯体高度、芯格内径对隔热性能的影响,并以此总结出蜂窝的隔热机理。研究结果表明:气凝胶可有效地提高蜂窝隔热性能;芯格壁厚越小,芯体高度越大,蜂窝隔热性能越好;填充气凝胶时,芯格内径越大隔热性能越好,蜂窝芯空腔时,芯格内径越大,隔热性能越差。

关键词：铌合金蜂窝气凝胶填充有限元模型几何参数隔热机理

Thermodynamic theory of flotation for a complex multiphase solid -liquid system and high-entropy flotation

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1177-1197页

作者： Shuming wen State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China

The flotation of complex solid–liquid multiphase systems involve interactions among multiple components,the core problem facing flotation theory.Meanwhile,the combined use of multicomponent flotation reagents to improve mineral flotation has become an important issue in studies on the efficient use of refractory mineral resources.However,studying the flotation of complex solid–liquid systems is extremely difficult,and no systematic theory has been developed to date.In addition,the physical mechanism associated with combining reagents to improve the flotation effect has not been unified,which limits the development of flotation theory and the progress of flotation technology.In this study,we applied theoretical thermodynamics to a solid–liquid flotation system and used changes in the entropy and Gibbs free energy of the reagents adsorbed on the mineral surface to establish thermodynamic equilibrium equations that de-scribe interactions among various material components while also introducing adsorption equilibrium constants for the flotation reagents adsorbed on the mineral surface.The homogenization effect on the mineral surface in pulp solution was determined using the chemical potentials of the material components of the various mineral surfaces required to maintain balance.The flotation effect can be improved through synergy among multicomponent flotation reagents;its physical essence is the thermodynamic law that as the number of compon-ents of flotation reagents on the mineral surface increases,the surface adsorption entropy change increases,and the Gibbs free energy change of adsorption decreases.According to the results obtained using flotation thermodynamics theory,we established high-entropy flotation theory and a technical method in which increasing the types of flotation reagents adsorbed on the mineral surface,increasing the adsorption entropy change of the flotation reagents,decreasing the Gibbs free energy change,and improving the adsorption efficiency and stability of the flotation reagents improve

关键词： multicomponent flotation reagent adsorption entropy change equations of thermodynamic equilibrium adsorption equilibri-um constant high-entropy flotation

Crack Prevention and Management Strategies in Bridge Engineering Construction

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Journal of World Architecture 2024年第2期8卷 67-71页

作者： yanzhen Lin Binzhou Municipal Public Development Service Center Binzhou 256600China

Cracking during construction is a common occurrence in modern bridge engineering that can directly impact the overall safety of the bridge.Therefore,it is essential to focus on preventing and controlling cracks.As the construction technology for bridge engineering has evolved,the internal quality of construction has significantly improved.However,the appearance quality remains a crucial factor that reflects the technical expertise of a construction company.Therefore,minimizing cracks and improving the appearance quality of concrete are critical issues that require the attention of construction units,supervision departments,and construction companies.This article will analyze the causes of cracking and suggest corresponding prevention and treatment methods.

关键词： Bridge engineering Engineering quality Quality management

Efficient reduction of Cr(Ⅵ)by guava(Psidium guajava)leaf extract and its mitigation effect on Cr toxicity in rice seedlings

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Journal of Environmental Sciences 2024年第7期141卷 1-15页

作者： Maodi Ran Yongqing Lu yanzhen Ren Li He Jiaokun Li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China

Hexavalent chromium(Cr(Ⅵ))is a toxic element that has negative impacts on crop growth and yield.Using plant extracts to convert toxic Cr(Ⅵ)into less toxic Cr(Ⅲ)may be a more favorable option compared to chemical reducing agents.In this study,the potential effects and mechanisms of using an aqueous extract of Psidium guajava L.leaves(AEP)in reducing Cr(Ⅵ)toxicity in rice were comprehensively studied.Firstly,the reducing power of AEP for Cr(Ⅵ)was confirmed by the cyclic voltammetry combined with X-ray photoelectron spectroscopy(XPS)assays.The highest Cr(Ⅵ)reduction efficiency reached approximately 78%under 1.5mg gallic acid equivalent(GAE)/mL of AEP and 10 mg/L Cr(Ⅵ)condition.Additionally,Cr(Ⅵ)stress had a significant inhibitory effect on rice growth.However,the exogenous application of AEP alleviated the growth inhibition and oxidative damage of rice under Cr(Ⅵ)stress by increasing the activity and level of enzymatic and non-enzymatic antioxidants.Furthermore,the addition of AEP restored the ultrastructure of root cells,promoted Cr adsorption onto root cell walls,and limited the translocation Cr to shoots.In shoots,AEP application also triggered the expression of specific genes involved in Cr defense and detoxification response,including photosynthesis pathways,antioxidant systems,flavonoids biosynthesis,and plant hormone signal transduction.These results suggest that AEP is an efficient reduction agent for Cr(Ⅵ),and exogenous application of AEP may be a promising strategy to mitigate the harm of Cr(Ⅵ)on rice,ultimately contributing to improved crop yield in Crcontaminated environments.

关键词： Hexavalent chromium Plant extract Reduction Rice plants Mechanisms

Goal-Oriented Control Systems(GOCS):From HOW to WHAT

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 816-819页

作者： wen-Hua Chen the Department of Aeronautical and Automotive Engineering Loughborough UniversityLeicestershireLE113TUU.K.

Brief:New control theory is required to underpin safe design and deployment of future highly automated systems to deal with uncertain environments and complicated tasks,enabled by AI and other advanced technologies.Goal-Oriented Control Systems offer potential to transform the control system design from currently instructing a control system how to perform a task to specifying what is to be achieved.

关键词： automated instru system

Genomic surveillance of emerging SARS-CoV-2 Omicron variations in Tianjin Municipality, China 2022

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Biosafety and Health 2024年第2期6卷 61-69页

作者： Xin Gao Ming Zou Yue Lei Zhaolin Tan Zhichao Zhuang Baolu Zheng Aiping Yu yanzhen Han Xiaohui Lu Xiaochang Liu Ying Wang Yuan Wang Liru Guo Guangwen Liu wen Li Yang Liu Likun Lv Peiyong Ning Xiaoyan Li Tianjin Centers for Disease Control and Prevention Tianjin 300011China Tianjin Key Laboratory of Pathogenic Microbiologyof Infectious Disease Tianjin Centers for Disease Controland PreventionTianjin 300011China

The coronavirus disease 2019(COvID-19)pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has severely impacted public health.In 2022,the Omicron variant of SARS-CoV-2 rapidly became the dominant circulating variant in the local COVID-19 outbreaks in Tianjin Municipality,China.To gain a deeper understanding of the genetic variations of the Omicron variant in Tianjin,specimens from indi-viduals who tested positive for SARS-CoV-2 between December 2021 and November 2022 were used for virus whole genome sequencing and phylogenetic analysis.A total of 1,674 high-quality Omicron sequences were obtained,consisting of 1,339 sequences from local cases belonging to 20 Phylogenetic Assignment of Named Global Outbreak(PANGO)lineages and 335 sequences from imported cases belonging to 70 lineages.Tianjin experienced five waves of local outbreaks,accompanied by multiple substitutions among subvariants,ranging from the initial BA.1.1 lineage to the subsequent BA.2,BF.7,and BA.5.2 lineages.The evolutionary rate of local strains,estimated to be 28.999 substitutions per year,and the evolutionary rate of imported strains,estimated to be 24.946 substitutions per year,were lower than that of the strains circulating globally.The addi-tional substitutions and deletions of local strains have been used to identify and disrupt the virus transmission chains.The subvariants such as BA.5.2.48,BA.5.2.49,BF.7.14,and XBB.1 circulating in the fifth epidemic wave presented criterial immune escape mutations including S:R346T,S:L452R and S:F486V.It is essential to implement genomic surveillance strategies to investigate further the development of genomic mutation char-acteristics in the SARS-CoV-2 variant.This ongoing monitoring will contribute to a better understanding of the virus's genetic changes and aid in effective control measures.

关键词： Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) Coronavirus disease 2019(COVID-19) Omicron variant Whole genome sequencing(WGS)