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Insight into the green route to dimethyl succinate by direct esterification of bio-based disodium succinate using CO_(2)and CH_(3)OH

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Chinese Journal of Chemical Engineering 2023年第12期64卷 188-195页

作者： Yu-Gao Wang xiao-chen han Bao Gu Hua-Shuai Wu Jun Shen School of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China

The fermentation for succinic acid production outperforms other methods by low energy consumption and environmental benignity,with the resulting products mainly as disodium succinate(DSA).By directly esterifying DSA using CO_(2) and CH3OH,it is expected to avoid the use of inorganic *** high-resolution mass spectrometry analysis and theoretical calculation,this study establishes that the reaction consists of three steps,i.e.,first forming 3-carboxypropanoate,then monomethyl succinate(MMS),and finally dimethyl succinate(DMS).A detailed kinetic analysis is further performed,the results demonstrate that the transformation of DSA to MMS is regarded to be a second-order reaction for reactant DSA,while the transformation of MMS to DMS is a first-order reaction for reactant *** activation energy for the generation of MMS from DSA is 37.15 kJ·mol^(-1),and that for the generation of DMS from MMS is 85.80 kJ·mol^(-1),indicating the latter one is the rate-determining step.

关键词： Succinate Carbon dioxide Direct esterification Reaction mechanism Reaction kinetics Kinetic modeling

Resilience effects for household food expenditure and dietary diversity in rural western China

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Journal of Integrative Agriculture 2024年第2期23卷 384-396页

作者： xiao han Kaiyu Lyu Fengying Nie Yuquan chen Institute of Agricultural Economics and Development Chinese Academy of Agricultural SciencesBeijing 100081China Agricultural Information Institute Chinese Academy of Agricultural SciencesBeijing 100081China Academy of Global Food Economics and Policy China Agricultural UniversityBeijing 100083China

A more resilient livelihood is increasingly recognized as an efficient way to improve vulnerable households’food security and optimize their dietary *** study quantifies rural household resilience in western China,identifies the three pillars(absorptive capacity,adaptive capacity,and transformative capacity)contribution to resilience,and then establishes the estimated Resilience Capacity Index(RCI)linked with food security and dietary diversity supported by the multiple indicator multiple cause(MIMIC)*** show that,despite geographical heterogeneity,the RCI consistently increased from 2015 to *** with a higher RCI inheriting better capacity to deal with risk and shocks are significantly and positively correlated with increasing food expenditure and diversifying food *** can be because resilient households will allocate more money to food expenditure instead of saving for livelihood ***,policymakers can provide more incentives for rural households to adopt more dynamic and effective risk management ***,in turn,could yield positive spillover effects by preventing human capital loss associated with dietary-related chronic diseases and mortality.

关键词： resilience food expenditure dietary diversity China risk management

Development and application of novel high‐efficiency composite ultrafine cement grouts for roadway in fractured surrounding rocks

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Deep Underground Science and Engineering 2024年第1期3卷 53-69页

作者： Maolin Tian Shaojie chen Lijun han Hongtian xiao Shandong Key Laboratory of Civil Engineering Disaster Prevention and Mitigation Shandong University of Science and TechnologyQingdaoChina College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdaoChina College of Energy and Mining Engineering Shandong University of Science and TechnologyQingdaoChina State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhouChina

The fractured surrounding rocks of roadways pose major challenges to safe *** has often been used to reinforce the surrounding rocks to mitigate the safety risks associated with fractured *** aim of this study is to develop highly efficient composite ultrafine cement(CUC)grouts to reinforce the roadway in fractured surrounding *** materials used are ultrafine cement(UC),ultrafine fly ash(UF),ultrafine slag(US),and additives(superplasticizer[SUP],aluminate ultrafine expansion agent[AUA],gypsum,and retarder).The fluidity,bleeding,shrinkage,setting time,chemical composition,microstructure,degree of hydration,and mechanical property of grouting materials were evaluated in this ***,a suitable and effective CUC grout mixture was used to reinforce the roadway in the fractured surrounding *** results have shown that the addition of UF and US reduces the plastic viscosity of CUC,and the best fluidity can be obtained by adding 40%UF and 10%*** UC and UF particles are small,the pozzolanic effect of UF promotes the hydration reaction,which is conductive to the stability of CUC *** addition,fine particles of UC,UF,and US can effectively fill the pores,while the volumetric expansion of AUA and gypsum decreases the pores and thus affects the microstructure of the solidified *** compressive test results have shown that the addition of specific amounts of UF and US can ameliorate the mechanical properties of CUC ***,the CUC22‐8 grout was used to reinforce the No.20322 belt *** results of numerical simulation and field monitoring have indicated that grouting can efficaciously reinforce the surrounding rock of the *** this research,high‐performance CUC grouts were developed for surrounding rock reinforcement of underground engineering by utilizing UC and some additives.

关键词： broken surrounding rock composite ultrafine cement(CUC)grouts grouting material grouting performance grouting reinforcement

无创冠状动脉生理功能评估技术对慢性冠脉综合征治疗价值的研究

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实用医院临床杂志 2024年第2期21卷 159-163页

作者：高洁付明欢陶雪飞陈晓涵程标四川省医学科学院·四川省人民医院四川成都610072

目的研究无创冠状动脉生理功能评估技术(FFRCT)指导慢性冠脉综合征(CCS)治疗的价值。方法纳入150例稳定胸痛并拟行冠状动脉造影(ICA)检查的CCS患者,采用随机数字法分为ICA组、FFR组及FFRCT组各50例。ICA组根据冠脉造影提示狭窄≥70%的... 详细信息

目的研究无创冠状动脉生理功能评估技术(FFRCT)指导慢性冠脉综合征(CCS)治疗的价值。方法纳入150例稳定胸痛并拟行冠状动脉造影(ICA)检查的CCS患者,采用随机数字法分为ICA组、FFR组及FFRCT组各50例。ICA组根据冠脉造影提示狭窄≥70%的病变进行经皮冠脉介入术(PCI),FFR组对冠脉造影提示狭窄≥50%且FFR值0.05)。FFRCT组不良事件的发生率低于ICA组和FFR组(P<0.05)。结论FFRCT诊断CCS具有较高的敏感度和特异度,可明显降低支架植入数量,减少CCS患者心血管不良事件发生率。

关键词：无创冠状动脉生理功能评估技术慢性冠脉综合征人工智能心血管不良事件

Improved nuclear mass formula with an additional term from the Fermi gas model

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Nuclear Science and Techniques 2024年第5期35卷 131-138页

作者： xiao-Yu Xu Li Deng Ai-Xi chen hang Yang Amir Jalili han-Kui Wang School of Science Zhejiang Sci-Tech UniversityHangzhou 310018China

Nuclear mass is a fundamental property of nuclear physics and a necessary input in nuclear *** to the complexity of atomic nuclei and nonperturbative strong interactions,conventional physical models cannot completely describe nuclear binding *** this study,the mass formula was improved by considering an additional term from the Fermi gas *** nuclear masses in the Atomic Mass Evaluation Database were reproduced with a root-mean-square deviation(RMSD)of -1.86 MeV(1.92 MeV).The new mass formula exhibits good performance in the neutron-rich nuclear *** RMSD decreases to 0.393 MeV when the ratio of the neutron number to the proton number is≥1.6.

关键词： Nuclear mass formula Neutron-rich nuclei Fermi-gas model

Identification of hub genes associated with Helicobacter pylori infection and type 2 diabetes mellitus:A pilot bioinformatics study

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World Journal of Diabetes 2024年第2期15卷 170-185页

作者： han chen Guo-Xin Zhang xiao-Ying Zhou Department of Gastroenterology The First Affiliated Hospital of Nanjing Medical UniversityNanjing 210003Jiangsu ProvinceChina Department of Gastroenterology Jiangsu Province HospitalNanjing 210029Jiangsu ProvinceChina

BACKGROUND Helicobacter pylori(***)infection is related to various extragastric diseases including type 2 diabetes mellitus(T2DM).However,the possible mechanisms connecting *** infection and T2DM remain *** To explore potential molecular connections between *** infection and *** We extracted gene expression arrays from three online datasets(GSE60427,GSE27411 and GSE115601).Differentially expressed genes(DEGs)commonly present in patients with *** infection and T2DM were *** genes were validated using human gastric biopsy *** between hub genes and immune cell infiltration,miRNAs,and transcription factors(TFs)were further *** A total of 67 DEGs were commonly presented in patients with *** infection and *** significantly upregulated hub genes,including TLR4,ITGAM,C5AR1,FCER1G,and FCGR2A,were finally identified,all of which are closely related to immune cell *** gene-miRNA analysis detected 13 miRNAs with at least two gene ***-gene interaction networks showed that TLR4 was coregulated by 26 TFs,the largest number of TFs among the 5 hub *** We identified five hub genes that may have molecular connections between *** infection and *** study provides new insights into the pathogenesis of ***-induced onset of T2DM.

关键词： Helicobacter pylori Type 2 diabetes mellitus Bioinformatics analysis Differentially expressed genes Hub genes

Air pressure law of a reservoir constructed in karst sinkholes

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Journal of Mountain Science 2024年第3期21卷 1048-1057页

作者： YU Bo TAI Shengping ZHENG Kexun chen Shiwan han xiao WANG Senlin ZUO Shuangying Power China Guiyang Engineering Corporation Limited Guiyang 550081China College of Resources and Environmental Engineering Key Laboratory of Karst Georesources and EnvironmentMinistry of EducationGuizhou UniversityGuiyang 550025China

Karst sinkholes with natural negative landform provide favorable conditions for the pumped storage reservoir construction for less excavation ***,the construction of the reservoir would plug the natural karst channels for water and air,which would cause remarkable air pressure in karst channels when the groundwater level fluctuates.A large laboratory simulation test was carried out to study the air pressure variation of a reservoir built on the karst *** air pressure in the karst channel and inside the model was monitored during the groundwater rising and falling *** showed that the variation of air pressure in the karst channel and the surrounding rock exhibited a high degree of *** air pressure increased rapidly at the initial stage of water level rising,followed by a slight decrease,then the air pressure increased sharply when the water level approached the top of the karst *** initial peak of air pressure and the final peak of air pressure were defined,and both air pressure peaks were linearly increasing with the water level rising *** negative air pressure was also analyzed during the drainage process,which was linearly correlated with the water level falling *** causes of air pressure variation in karst channels of a pumped storage reservoir built on the karst sinkhole were *** initial rapid increase,then slight decrease and final sudden increase of air pressure were controlled by the combined effects of air compression in karst channel and air seepage into the surrounding *** the drainage process,the instant negative air pressure and gradual recovering of air pressure were controlled by the combined effects of negative air pressure induced by water level falling and air supply from surrounding *** work could provide valuable reference for the reservoir construction in karst area.

关键词： Simulation test Karst sinkhole Pumped storage reservoir Air pressure Flow rate

An efficient parallel algorithm of variational nodal method for heterogeneous neutron transport problems

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Nuclear Science and Techniques 2024年第4期35卷 29-45页

作者： han Yin xiao-Jing Liu Teng-Fei Zhang School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 2002040China

The heterogeneous variational nodal method(HVNM)has emerged as a potential approach for solving high-fidelity neutron transport ***,achieving accurate results with HVNM in large-scale problems using high-fidelity models has been challenging due to the prohibitive computational *** paper presents an efficient parallel algorithm tailored for HVNM based on the Message Passing Interface *** algorithm evenly distributes the response matrix sets among processors during the matrix formation process,thus enabling independent construction without *** the formation tasks are completed,a collective operation merges and shares the matrix sets among the *** the solution process,the problem domain is decomposed into subdomains assigned to specific processors,and the red-black Gauss-Seidel iteration is employed within each subdomain to solve the response matrix ***-to-point communication is conducted between adjacent subdomains to exchange data along the *** accuracy and efficiency of the parallel algorithm are verified using the KAIST and JRR-3 test *** results obtained with multiple processors agree well with those obtained from Monte Carlo *** parallelization of HVNM results in eigenvalue errors of 31 pcm/-90 pcm and fission rate RMS errors of 1.22%/0.66%,respectively,for the 3D KAIST problem and the 3D JRR-3 *** addition,the parallel algorithm significantly reduces computation time,with an efficiency of 68.51% using 36 processors in the KAIST problem and 77.14% using 144 processors in the JRR-3 problem.

关键词： Neutron transport Variational nodal method Parallelization KAIST JRR-3

Bioinspired nanomaterials for wearable sensing and human–machine interfacing

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Nano Research 2024年第2期17卷 445-461页

作者： Vishesh Kashyap Junyi Yin xiao xiao Jun chen Department of Bioengineering University of CaliforniaLos AngelesLos AngelesCA 90095USA Department of Mechanical and Aerospace Engineering University of CaliforniaLos AngelesLos AngelesCA 90095USA

The inculcation of bioinspiration in sensing and human–machine interface(HMI)technologies can lead to distinctive characteristics such as conformability,low power consumption,high sensitivity,and unique properties like self-healing,self-cleaning,and *** sensing and HMI are fields rife with opportunities for the application of bioinspired nanomaterials,particularly when it comes to wearable sensory systems where biocompatibility is an additional *** review discusses recent development in bioinspired nanomaterials for wearable sensing and HMIs,with a specific focus on state-of-the-art bioinspired capacitive sensors,piezoresistive sensors,piezoelectric sensors,triboelectric sensors,magnetoelastic sensors,and electrochemical *** also present a comprehensive overview of the challenges that have hindered the scientific advancement in academia and commercialization in the industry.

关键词： bioinspired nanomaterials human–machine interface wearable sensors wearable bioelectronics