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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 357-381页

作者： yakun zhang Guofang GONG Huayong YANG Jianbin LI Liujie JING State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China China Railway Engineering Equipment Group Co. Lid.Zhengzhou 450016China Maha Fluid Power Research Center Purdue UniversityWest LafayetteIN 47905USA

Advances in intelligent shield machines reflect an evolving trend from traditional tunnel boring machines(TBMs)to tunnel boring robots(TBRs).This shift aims to address the challenges encountered by the conventional shield machine industry arising from construction environment and manual operations.This study presents a systematic review of intelligent shield machine technology,with a particular emphasis on its smart operation.Firstly,the definition,meaning,contents,and development modes of intelligent shield machines are proposed.The development status of the intelligent shield machine and its smart operation are then presented.After analyzing the operation process of the shield machine,an autonomous operation framework considering both stand-alone and fleet levels is proposed.Challenges and recommendations are given for achieving autonomous operation.This study offers insights into the essence and developmental framework of intelligent shield machines to propel the advancement of this technology.

关键词： Intelligent shield machine Tunnel boring machine(TBM) Tunnel boring robot(TBR) Self-driving Autonomous control Shield machine

Cu single atoms embedded on hollow g-C_(3)N_(4)nanospheres with enhanced charge transfer and separation for efficient photocatalysis

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Chinese Chemical Letters 2024年第2期35卷 455-459页

作者： Linlin zhang Jianjun Liao yakun Li Wei Sun Chengjun Ge Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province School of Ecology and EnvironmentHainan UniversityHaikou 570228China Shandong Ocean Chemical Industry Scientific Research Institute Weifang 262737China

Establishing an effective charge transfer mechanism in carbon nitride(g-C_(3)N_(4))to enhance its photocatalytic activity remains a limiting nuisance.Herein,the combination design of a single Cu atom with hollow g-C_(3)N_(4)nanospheres(Cu-N_(3)structure)has been proven to offer significant opportunities for this crucial challenge.Moreover,this structure endows two pathways for charge transfer in the reaction,namely,the N atoms in the three-dimensional planar structure are only bonded with a single Cu atom,and charge transfer occurs between the plane and the layered structure due to the bending of the interlayered g-C_(3)N_(4)hollow nanospheres.Notably,Cu-N_(3)and hollow nanosphere structures have been certified to greatly enhance the efficiency of photogenerated carrier separation and transfer between the layers and planes by ultrafast spectral analysis.As a result,this catalyst possesses unparalleled photocatalytic efficiency.Specifically,the hydrogen production rate up to 2040μmol h^(−1) g^(−1),which is 51 times that of pure C_(3)N_(4)under visible light conditions.The photocatalytic degradation performance of tetracycline and oxidation performance of benzene is also expressed,with a degradation rate of 100%,a conversion of 97.3%and a selectivity of 99.9%.This work focuses on the structure-activity relationship to provide the possibilities for the development of potential photocatalytic materials.

关键词： g-C_(3)N_(4) Cu single atom Hollow nanospheres Charge transfer pathways Photocatalytic hydrogen production

Cobalt-doped TiO_(2)@C hierarchical nanocomposites derived from Ti_(3)C_(2) MXene as cathodes for hybrid magnesium-lithium batteries

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Nano Research 2024年第1期17卷 253-261页

作者： Xiaohui Li yakun Tang Lang Liu Yue zhang Yang Gao Mao Qian Wenjie Ma State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830017China

TiO_(2)has been explored in hybrid magnesium-lithium batteries(HMLBs)due to the advantages of low self-discharge and small volume expansion during ion insertion.However,how to improve the inherently low ionic and electrical conductivity of TiO_(2)is the problem that needs to be solved.In this work,a smart strategy is adopted to prepare cobalt-doped TiO_(2)@C(Co^(4+)-TiO_(2)@C)hierarchical nanocomposite derived from Co(II)(OH)n@Ti3C2.Compared with TiO_(2)@C(without cobalt doping),Co^(4+)-TiO_(2)@C shows the highest specific capacity(154.7 mAh·g^(-1)at 0.1 A·g^(-1)after 200 cycles)and extraordinary rate performance in HMLBs.The excellent electrochemical performance of Co4+-TiO_(2)@C is ascribed to the synergistic effect of the hierarchical structure and cobalt-doping.Both experimental results and density functional theory(DFT)calculation reveal that the cobalt-doping has effectively improved the electronic conductivity and reduced the Li+migration barrier.This work provides a new insight to design TiO_(2)-based cathode materials with high-performance in HMLBs.

关键词： Ti_(3)C_(2)MXene TiO_(2) hybrid magnesium-lithium batteries hierarchical structure cobalt-doping

Long-range Pt-Ni dual sites boost hydrogen evolution through optimizing the adsorption configuration

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Nano Research 2024年第5期17卷 3700-3706页

作者： Cong Liu Pengfang zhang Bing Liu Qian Meng Xuzhao Yang yakun Li Jingli Han Yao Wang Henan Province Engineering Research Center of Catalysis and Separation of Cyclohexanol College of Materials and Chemical EngineeringZhengzhou University of Light IndustryZhengzhou 450001China Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology Liaocheng UniversityLiaocheng 252000China Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringInternational Joint Research Center for Photoresponsive Molecules and MaterialsJiangnan UniversityWuxi 214122China

Elaborated design of catalytic systems with a specifically tailored site distance to match the intermediates could substantially improve reaction kinetics and boost catalytic activity under unfavorable reaction conditions.Considering the lower energy barriers of water splitting upon the synergy of dual sites,constructing synergistic Pt-M(M:transition metal)dual sites is an effective way to boost Pt with highly catalytic hydrogen evolution reaction(HER)performance.An unconventional“Ni(OH)_(2)-coated high-index Pt facets”was constructed to obtain long-range Pt-Ni dual sites,in which Ni composition as a water dissociation synergistic site can protect Pt from electrolyte corrosion and ensure efficient proton donation to Pt sites.The obtained long-range Pt-Ni dual sites present 3.84 mA·cm^(-1) of current density,which is 7.5 times specific activity higher than that of commercial Pt/C towards alkaline HER.The enhanced HER performance is attributed to synergistic catalysis on Pt-Ni dual sites accompanied by unconventional electron coupling.This work illustrates a new strategy to construct the long-range dual sites by unconventional strategy for fundamental electrocatalytic study of alkaline HER.

关键词： long-range Pt-Ni dual sites electron transfer hydrogen evolution reaction sites synergy

Using pXRF and vis-NIR spectra for predicting properties of soils developed in loess

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Pedosphere 2022年第4期32卷 602-615页

作者： Gafur GOZUKARA yakun zhang Alfred E.HARTEMINK University of Wisconsin-Madison Department of Soil ScienceFD Hole Soils Lab1525 Observatory DriveMadison WI 53706USA Eskisehir Osmangazi University Department of Soil Science and Plant NutritionEskisehir 26160Turkey

Visible near-infrared (vis-NIR) and portable X-ray fluorescence (pXRF) spectrometers have been increasingly utilized for predicting soil properties worldwide. However, only a few studies have focused on splitting the predictive models by horizons to evaluate prediction performance and systematically compare prediction performance for A, B, and combined A+B horizons. Therefore, we investigated the performance of pXRF and vis-NIR spectra, as individual or combined, for predicting the clay, silt, sand, total carbon (TC), and pH of soils developed in loess, and compared their prediction performance for A, B, and A+B horizons. Soil samples (176 in A horizon and 172 in B horizon) were taken from Mollisols and Alfisols in 136 pedons in Wisconsin, USA and analyzed for clay, silt, sand, pH, and TC. The pXRF and vis-NIR spectrometers were used to measure the pXRF and vis-NIR soil spectra. Data were separated into calibration (n = 244, 70%) and validation (n = 104, 30%) datasets. The Savitzky-Golay filter was applied to preprocess the pXRF and vis-NIR spectra, and the first 10 principal components (PCs) were selected through principal component analysis (PCA). Five types of predictor, i.e., PCs from vis-NIR spectra, pXRF of beams at 0–40 and 0–10 keV (XRF40 and XRF10, respectively) spectra, combined XRF40 and XRF10 (XRF40+XRF10) spectra, and combined XRF40, XRF10, and vis-NIR (XRF40+XRF10+vis-NIR) spectra, were compared for predicting soil properties using a machine learning algorithm (Cubist model). A multiple linear regression (MLR) model was applied to predict clay, silt, sand, pH, and TC using pXRF elements. The results suggested that pXRF spectra had better prediction performance for clay, silt, and sand, whereas vis-NIR spectra produced better TC and pH predictions. The best prediction performance for sand (R2= 0.97), silt (R2= 0.95), and clay (R2= 0.84) was achieved using vis-NIR+XRF40+XRF10 spectra in B horizon, whereas the best prediction performance for TC (R2= 0.93) and pH (R2= 0.79) was achieved using vis-NIR+XR

关键词： Cubist model machine learning algorithm portable X-ray fluorescence spectra soil elements visible near-infrared spectra

Influence of stir-frying on the lipid stability and flavor substances in oat flour during storage using HS-SPME-GC-MS and electronic nose

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Food Quality and Safety 2023年第1期7卷 30-39页

作者： Yuanyuan zhang Meili zhang Xue Bai yakun zhang Jing zhang Rui Huo College of Food Science and Engineering Inner Mongolia Agricultural UniversityHuhhotChina Agricultural and Livestock Products Processing Research Institute Inner Mongolia Academy of Agricultural and Animal Husbandry SciencesHuhhotChina

Objectives:We used stir-fried oat flour as experimental material and raw oat flour as a control to explore the influence of stir-frying on the storagequalityofoatflour.Materials and Methods:The HS-SPME-GC-MS method combined with electronic nose technology was used to understand the lipid stability and analyze the changes in the flavor of the substances during the entire storage period.Results:It was observed that during the storage period,stir-fried oat flour contained less water than raw oat flavor.The former was characterized by a lower fatty acid value,lower acid value,and lower linoleic acid content,but higher oleic acid content and palmitic acid content compared to the latter.With the passage of storage time,the palmitic acid content significantly increased,and the linoleic acid content significantly decreased in raw and stir-fried oats flour(P

关键词： Stir-frying oat flour lipid stability flavor substances storage

The impact of high hydrostatic pressure treatment time on the structure,gelatinization and thermal properties and in vitro digestibility of oat starch

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Grain & Oil Science and Technology 2022年第1期5卷 1-12页

作者： Jing zhang Meili zhang Xue Bai yakun zhang Chen Wang College of Food Science and Engineering Inner Mongolia Agricultural UniversityHuhhot 010018China Sanya Research Institute Hainan Academy of Agricultural SciencesSanya 572024China

As a non-thermal processing technology,high hydrostatic pressure(HHP)can be used for starch modification without affecting the quality and flavour constituents.The effect of HHP on starch is closely related to the treatment time of HHP.In this paper,we investigated the impacts of HHP treatment time(0,5,10,15,20,25,30 min)on the microstructure,gelatinization and thermal properties as well as in vitro digestibility of oat starch by scanning electron microscopy,X-ray diffraction,Fourier transform infrared spectroscopy,13C NMR and differential scanning calorimeter.Results showed that 5-min HHP treatment led to deformation and decreases in short-range ordered and doublehelix structures of oat starch granules,and further extending the treatment time to 15 min or above caused the formation of a gelatinous connection zone,increase of particle size,disintegration of short-range ordered and double-helix structures,and crystal structure change from A type to V type,indicating gelatinization occurred.Longer treatment time also resulted in the reduction in both the viscosity and the stability of oat starch.These indicated that HHP treatment time greatly influenced the microstructure of oat starch,and the oat starch experienced crystalline destruction(5 min),crystalline disintegration(15 min)and gelatinization(>15 min)during HHP treatment.Results of in vitro digestibility showed that the rapidly digestible starch(RDS)content declined first after treatment for 5 to 10 min then rose with the time extending from 15 to 30 min,indicating that longer pressure treatment time was unfavourable to the health benefits of oat starch for humans with diabetes and cardiovascular disease.Therefore,the 500-MPa treatment time for oat starch is recommended not more than 15 min.This study provides theoretical guidance for the application of HHP technology in starch modification and development of health foods.

关键词： High hydrostatic pressure Oat starch Structure Gelatinization property Thermal property In vitro digestibility

Helicobacter pylori and immunotherapy for gastrointestinal cancer

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The Innovation 2024年第2期5卷 51-60页

作者： Keren Jia Yang Chen Yi Xie Xicheng Wang Yajie Hu Yu Sun Yanshuo Cao Liyan zhang yakun Wang Zhenghang Wang Zhihao Lu Jian Li Xiaotian zhang Lin Shen Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of Gastrointestinal OncologyPeking University Cancer Hospital&InstituteBeijing 100142China Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of PathologyPeking University Cancer Hospital&InstituteBeijing 100142China

Helicobacter pylori infection is associated with the risk of gastrointestinal(GI)cancers;however,its impact on immunotherapy for GI cancers remains uncertain.In this study,we included 10,122 patients who underwent ^(13)C-urea breath tests.Among 636 patients with Epstein-Barr virus–negative microsatellite-stable gastric cancer(GC)who were treated with anti-PD-1/PD-L1 therapy,H.pylori–positive patients exhibited significantly longer immune-related progression-free survival(irPFS)compared with H.pylori–negative patients(6.97 months versus 5.03 months,p<0.001,hazard ratio[HR]0.76,95%confidence interval[CI]0.62–0.95,p=0.015).Moreover,the H.pylori–positive group demonstrated a trend of 4 months longer median immune-related overall survival(irOS)than the H.pylori–negative group.H.pylori–positive GC displayed higher densities of PD-L1+cells and nonexhausted CD8+T cells,indicative of a“hot”tumor microenvironment.Transcriptomic analysis revealed that H.pylori–positive GC shared molecular characteristics similar to those of immunotherapy-sensitive GC.However,H.pylori–positive patients with DNA mismatch repair–deficient(dMMR)/microsatellite instability–high(MSI-H)colorectal adenocarcinoma and esophageal squamous cell carcinoma(ESCC)had shorter irPFS compared with H.pylori–negative patients(16.13 months versus not reached,p=0.042,HR 2.26,95%CI 1.13–4.50,p=0.021 and 5.57 months versus 6.97 months,p=0.029,HR 1.59,95%CI 1.14–2.23,p=0.006,respectively).The difference in irOS between H.pylori–positive and–negative patients had the same trend as that between dMMR/MSI-H colorectal adenocarcinoma and ESCC patients.We also identified a trend of shorter irPFS and irOS in H.pylori–positive liver cancer and pancreatic cancer patients.In summary,our findings supported that H.pylori infection is a beneficial factor for GC immunotherapy by shaping hot tumor microenvironments.However,in dMMR/MSI-H colorectal adenocarcinoma and ESCC patients,H.pylori adversely affects the efficacy of immunotherapy.

关键词： immunotherapy gastrointestinal pylori

The impact of landslides on chemical and microbial properties of soil in a temperate secondary forest ecosystem

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Journal of Forestry Research 2022年第6期33卷 1913-1923页

作者： yakun zhang Chen Miao Jiaojun Zhu Tian Gao Yirong Sun Jinxin zhang Shuang Xu Kai Yang Qingyuan Forest CERN Institute of Applied EcologyChinese Academy of SciencesShenyang 110016People’s Republic of China CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

In forest ecosystems,landslides are one of the most common natural disturbances,altering the physical,chemical and microbial characteristics of soil and thus further altering ecosystem properties and processes.Although secondary forests comprise more than 50%of global forests,the influence of landslides on the soil properties in these forests is underappreciated.Therefore,this study investigates the influence of landslides on the chemical and microbial nature of the soil.Study of these modifications is critical,as it provides baseline evidence for subsequent forest revegetation.We selected four independent landslides and adjacent secondary forest stands as references in a temperate secondary forest in northeastern China.Soils were obtained from each stand at 0–10 cm and 10–20 cm depths to determine chemical and microbial properties.Soil total carbon(TC),total nitrogen(TN),nitrate(NO_(3)^(-)-N),available phosphorus(P),microbial biomass carbon(MBC),microbial biomass nitrogen(MBN),microbial biomass phosphorus(MBP)and phenol oxidase,exoglucanase,β-glucosidase,N-acetyl-β-glucosaminidase,L-asparaginase and acid phosphatase activities were 29.3–70.1%lower at the 0–10 cm soil depth in the landslide sites than at the secondary forest sites,whereas total phosphorus(TP)and ammonium(NH_(4)^(+)-N)were unaffected by the landslides.N-related enzymes,N-acetyl-β-glucosaminidase and L-asparaginase were reduced by more than 65%in the landslide sites,consistent with the decrease in nitrate concentration at the same 0–10 cm depth.At a depth of 10–20 cm,the variations in the soil properties were consistent with those at the 0–10 cm depth.The results demonstrated that soil chemical and microbial properties were significantly disrupted after the landslides,even though the landslides had occurred 6 years earlier.A long time is thus needed to restore the original C and nutrient levels.In temperate secondary forests,soil TC and TN contents were found to be more suitable for estimating the state of soil restoration than soil TP content.

关键词： Secondary forest Landslide Soil nutrients Microbial biomass Enzyme activity

Multi-class detection of cherry tomatoes using improved YOLOv4-Tiny

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International Journal of Agricultural and Biological Engineering 2023年第2期16卷 225-231页

作者： Fu zhang Zijun Chen Shaukat Ali Ning Yang Sanling Fu yakun zhang College of Agricultural Equipment Engineering Henan University of Science and TechnologyLuoyang 471023HenanChina Collaborative Innovation Center of Machinery Equipment Advanced Manufacturing of Henan Province Luoyang 471023HenanChina Wah Engineering College University of WahWah Cantt 47040Pakistan School of Electrical and Information Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina College of Physics Engineering Henan University of Science and TechnologyLuoyang 471023HenanChina

The rapid and accurate detection of cherry tomatoes is of great significance to realizing automatic picking by robots.However,so far,cherry tomatoes are detected as only one class for picking.Fruits occluded by branches or leaves are detected as pickable objects,which may cause damage to the plant or robot end-effector during picking.This study proposed the Feature Enhancement Network Block(FENB)based on YOLOv4-Tiny to solve the above problem.Firstly,according to the distribution characteristics and picking strategies of cherry tomatoes,cherry tomatoes were divided into four classes in the nighttime,and daytime included not occluded,occluded by branches,occluded by fruits,and occluded by leaves.Secondly,the CSPNet structure with the hybrid attention mechanism was used to design the FENB,which pays more attention to the effective features of different classes of cherry tomatoes while retaining the original features.Finally,the Feature Enhancement Network(FEN)was constructed based on the FENB to enhance the feature extraction ability and improve the detection accuracy of YOLOv4-Tiny.The experimental results show that under the confidence of 0.5,average precision(AP)of non-occluded,branch-occluded,fruit-occluded,and leaf-occluded fruit over the day test images were 95.86%,92.59%,89.66%,and 84.99%,respectively,which were 98.43%,95.62%,95.50%,and 89.33% on the night test images,respectively.The mean Average Precision(mAP)of four classes over the night test set was higher(94.72%)than that of the day(90.78%),which were both better than YOLOv4 and YOLOv4-Tiny.It cost 32.22 ms to process a 416×416 image on the GPU.The model size was 39.34 MB.Therefore,the proposed model can provide a practical and feasible method for the multi-class detection of cherry tomatoes.

关键词： cherry tomatoes deep learning data augmentation YOLOv4 occlusion multi-class detection