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三叶草根浸提液对3种牧草种子萌发及幼苗生长的影响

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陕西林业科技 2024年第3期52卷 1-6页

作者：俞靓谢治国董强杨波李群李军保陕西省林业科学院黄土高原水土保持与生态修复国家林业和草原局重点实验室西安710082

为探索三叶草的防控及利用提供理论依据,采用培养皿生物测定法分析,研究不同浓度(0、2.5、5.0、10.0 g·L-1)三叶草根浸提液对黑麦草(Lolium perenne)、高羊茅(Festuca arundinac)和赖草(Leymus secalinus)种子萌发及幼苗生长的化感作用... 详细信息

为探索三叶草的防控及利用提供理论依据,采用培养皿生物测定法分析,研究不同浓度(0、2.5、5.0、10.0 g·L-1)三叶草根浸提液对黑麦草(Lolium perenne)、高羊茅(Festuca arundinac)和赖草(Leymus secalinus)种子萌发及幼苗生长的化感作用,以及三叶草(Trifolium repens)的生长竞争力和成功入侵原因。结果表明,三叶草根浸提液对3种牧草种子萌发(发芽率、发芽指数)和幼苗生长(根长、苗长、根干重、苗干重)均有化感作用,且其化感作用效应存在一定的差异。三叶草根浸提液对黑麦草种子萌发具有抑制作用,对高羊茅和赖草的种子萌发有“低促高抑”作用,对黑麦草根长和干重、苗高和干重均具有抑制作用,对高羊茅和赖草则表现为低浓度的促进、高浓度的抑制效应。从综合化感效应指数来看,随着三叶草根浸提液浓度的增加,对黑麦草具有抑制作用,而对高羊茅和赖草有“低促高抑”的双重作用。3种供试牧草对三叶草根浸提液的敏感程度也有差异,表现为:黑麦草>高羊茅>赖草。入侵植物三叶草根浸提液对3种牧草的化感效应较为明显,在入侵严重的地方,可选择补播耐受力强的牧草。

关键词：三叶草浸提液黑麦草高羊茅赖草化感效应

TSC prediction and dynamic control of BOF steelmaking with state-of-the-art machine learning and deep learning methods

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Journal of Iron and Steel Research(International) 2024年第1期31卷 174-194页

作者： Tian-yi xie Cai-dong Zhang Quan-lin Zhou zhi-qiang Tian Shuai Liu Han-jie guo Material Technology Research Institute Hesteel GroupShijiazhuang050023HebeiChina Tangsteel Company Hesteel GroupTangshan063611HebeiChina School of Artificial Intelligence Beijing Technology and Business UniversityBeijing100048China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

Mathematical(data-driven)models based on state-of-the-art(SOTA)machine learning and deep learning models and data collected from 12,786 heats were established to predict the values of temperature,sample,and carbon(TSC)test,including temperature of molten steel(TSC-Temp),carbon content(TSC-C)and phosphorus content(TSC-P),which made prepa-ration for eliminating the TSC test.To maximize the prediction accuracy of the proposed approach,various models with different inputs were implemented and compared,and the best models were applied to the production process of a Hesteel Group steelmaking plant in China in the field.The number of tabular features(hot metal information,scrap,additives,blowing practices,and preset values)was expanded,and time series(off-gas profiles and blowing practice curves)that could reflect the entire steelmaking process were introduced as inputs.First,the latest machine learning models(LightGBM,CatBoost,TabNet,and NODE)were used to make predictions with tabular features,and the best coefficient of determination R^(2)values obtained for TSC-P,TSC-C and TSC-Temp predictions were 0.435(LightGBM),0.857(Cat-Boost)and 0.678(LightGBM),respectively,which were higher than those of classic models(backpropagation and support vector machine).Then,making predictions was performed by using SOTA time series regression models(SCINet,DLinear,Informer,and MLSTM-FCN)with original time series,SOTA image regression models(NesT,CaiT,ResNeXt,and GoogLeNet)with resized time series,and the proposed Concatenate-Model and Parallel-Model with both tabular features and time series.Through optimization and comparisons,it was finally determined that the Concatenate-Model with MLSTM-FCN,SCINet and Informer as feature extractors performed the best,and its R^(2)values for predicting TSC-P,TSC-C and TSC-Temp reached 0.470,0.858 and 0.710,respectively.Its field test accuracies for TSC-P,TSC-C and TSC-Temp were 0.459,0.850 and 0.685,respectively.A related importance analysis was carried out,and dynamic control methods based on pred

关键词： BOF steelmaking In-blow prediction TSC test Machine learning Deep learning Field application

High-Performance Recyclable Furan-based Epoxy Resin and Its Carbon Fiber Composites with Dense Hydrogen Bonding

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Chinese Journal of Polymer Science 2024年第1期42卷 73-86,I0008页

作者： Chang-Bo Zhao Lu-Kun Feng Hui xie Ming-Liang Wang Bing guo zhi-Yong Xue Cai-Zhen Zhu Jian Xu Advanced Materials Research Institute North China Electric Power UniversityBejing 102206China Institute of Low-Dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China School of Science and Shenzhen Key Laboratory of Flexible Printed Electronics Technology and Shenzhen Key Laboratory of Advanced Functional Carbon Materials Research and Comprehensive ApplicationHarbin Institute of TechnologyShenzhen 518055China

The emerging biomass-based epoxy vitrimers hold great potential to fulfill the requirements for sustainable development of society.Since the existence of dynamic chemical bonds in vitrimers often reduces both the thermal and mechanical properties of epoxy resins, it is challenging to produce recyclable epoxy vitrimers with both excellent mechanical properties and good thermal stability. Herein, a monomer 4-(((5-(hydroxymethyl)furan-2-yl)methylene)amino)phenol(FCN) containing furan ring with potential to form high density of hydrogen bonding among repeating units is designed and copolymerized with glycerol triglycidyl ether to yield epoxy resin(FCN-GTE), which intrinsically has dual hydrogen bond networks, dynamic imine structure and resultant high performance. Importantly, as compared to the BPA-GTE, the FCN-GTE exhibits significantly improved mechanical properties owing to the increased density of hydrogen bond network and physical crosslinking interaction. Furthermore, density functional theory(DFT) calculation and in situ FTIR analysis is conducted to decipher the formation mechanism of hydrogen bond network. In addition, the FCN-GTE possesses superior UV shielding, chemical degradation, and recyclability because of the existence of abundant imine bonds. Notably, the FCN-GTE-based carbon fiber composites could be completely recycled in an amine solution.This study provides a facile strategy for synthesizing recyclable biomass-based high-performance epoxy vitrimers and carbon fiber composites.

关键词： Furan Hydrogen bond network Dynamic Schiff base Carbon fiber composites Recycling

An NMOS output-capacitorless low-dropout regulator with dynamic-strength event-driven charge pump

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Journal of Semiconductors 2024年第6期45卷 23-34页

作者： Yiling xie Baochuang Wang Dihu Chen Jianping guo School of Electronics and Information Technology Sun Yat-sen UniversityGuangzhou 510006China School of Microelectronics University of Science and Technology of ChinaHefei 230000China

In this paper,an NMOS output-capacitorless low-dropout regulator(OCL-LDO)featuring dual-loop regulation has been proposed,achieving fast transient response with low power consumption.An event-driven charge pump(CP)loop with the dynamic strength control(DSC),is proposed in this paper,which overcomes trade-offs inherent in conventional structures.The presented design addresses and resolves the large signal stability issue,which has been previously overlooked in the event-driven charge pump structure.This breakthrough allows for the full exploitation of the charge-pump structure's poten-tial,particularly in enhancing transient recovery.Moreover,a dynamic error amplifier is utilized to attain precise regulation of the steady-state output voltage,leading to favorable static characteristics.A prototype chip has been fabricated in 65 nm CMOS technology.The measurement results show that the proposed OCL-LDO achieves a 410 nA low quiescent current(IQ)and can recover within 30 ns under 200 mA/10 ns loading change.

关键词： output-capacitorless low-dropout regulator fast transient low quiescent current event-driven charge pump

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陕西省湿地植物资源调查

陕西林业科技 2024年第3期52卷 100-105页

作者：高娅妮孙瑞鑫俞靓雷秀云赵恬武哲吴爱娇乔乐杨波马志林谢治国陕西省林业科学院西安710082 贵州省畜牧兽医研究所贵阳550002

为给陕西省湿地保护与管理提供参考,通过野外调查与查阅文献资料,对陕西省湿地植物进行统计分析。结果表明:陕西省现有湿地维管植物88科,259属,423种。其中,蕨类植物有3科4属5种;裸子植物有2科2属2种;被子植物有83科253属416种。草本植... 详细信息

为给陕西省湿地保护与管理提供参考,通过野外调查与查阅文献资料,对陕西省湿地植物进行统计分析。结果表明:陕西省现有湿地维管植物88科,259属,423种。其中,蕨类植物有3科4属5种;裸子植物有2科2属2种;被子植物有83科253属416种。草本植物尤其是岸边植物在数量上占绝大多数,其中禾本科、菊科、莎草科是陕西湿地植物中的优势物种。植物区系以世界分布型为主,温带分布型尤其是北温带分布型居多。同时,文章还分析了陕西省湿地植物保护中存在的问题,并对陕西省湿地植物资源保护提出对策建议。

关键词：湿地植物资源问题对策陕西省

Microstructure and mechanical properties of Ti/Al/Ti clad plates prepared via powder-in-tube method

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Journal of Iron and Steel Research(International) 2024年第3期31卷 670-687页

作者： Xian-lei Hu Qin-cheng xie Yi Yuan Ying zhi State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina Suzhou Dongbao Haixing Metal Material Technology Co. Ltd.Suzhou 215600JiangsuChina School of Material Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina

The Ti/Al/Ti clad plates exhibit a broad spectrum of potential applications.However,the conventional techniques of hot-pressing composite and explosive composite are intricate and environmentally hazardous.A novel method was introduced for preparing clad plates,namely,the powder-in-tube method.This method involves a combination of cold rolling,annealing at a temperature of 550℃,and double rolling.The morphology of the intermetallic compound layer was analyzed through the utilization of interface stripping test,tensile test,and microscopic characterization.The interface morphology,interface bonding properties,tensile fracture structures,and properties of plates under the first and second rolling were compared,along with the effects of intermetallic compounds on the interface properties.The results indicate that the powder-in-tube method,when annealed at 550℃,can produce a composite plate featuring a complete and uniform Ti/Al interface.The obtained plate exhibits a peeling strength of 21.5 N/mm,tensile strength of 424 MPa,and elongation of 11.5%.Furthermore,a systematic analysis was conducted to determine the causes of performance degra-dation observed during annealing at temperatures of 600 and 650℃.

关键词： Powder-in-tube method-Ti/Al/Ti clad plate Annealing Cold rolling-Mechanical property

Boost VS_(2) electrochemical reactive kinetics by regulating crystallographic planes and coupling carbon matrix for high performance sodium-ion storage

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Rare Metals 2024年第1期43卷 98-112页

作者： Min Zeng Ming-Shan Wang Lin Chen En-zhi Li Zhen-Liang Yang Dan Zhou Hai-Jiao xie Jun-Chen Chen zhi-Yuan Ma Bing-Shu guo Bo Yu Xing Li School of New Energy and Materials Southwest Petroleum UniversityChengdu 610500China Energy Storage Research Institute Southwest Petroleum UniversityChengdu 610500China Institute of Materials China Academy of Engineering PhysicsMianyang 621908China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and TechnologyBeijingBeijing 100083China Hangzhou Yanqu Information Technology Co. Ltd.Hangzhou 310003China

Vanadium disulfide(VS_(2)) as a typical two-dimensional transition metal chalcogenide has excellent competitiveness for sodium-ion storage due to its wide layer spacing(0.575 nm),high theoretical capacity of 932mAh·g^(-1) originating from multi-electron electrochemical redox.However,continuous sodiation process accompanied by crystal structural evolution and collapse cause rapid capacity decaying.Herein,novel few-layer VS_(2)nanosheets with open(001) crystal planes are in-situ constructed on reduced graphene oxide to solve these issues mentioned above.It indicates that few-layer VS_(2)provides more Na^(+) storage activity due to the low Na^(+)surface migration energy barrier on exposed crystal(001)planes.The flexible and high electronic conductivity of carbon matrix also effectively builds multi-level buffer structure and electron transport kinetics to boost the Na^(+)insertion/conversion reactive activity on VS_(2) as well as Na^(+) pseudocapacitance storage kinetics on edges and defects of nano sheets.Those coupling effects result in high rate capability and long cycling stability as a battery/capacitor anode.It delivers conspicuous high energy density of 81 and 40 Wh·kg^(-1) at power density of 118 and 10,286W·kg^(-1),as well as 80% energy retention rate after 5000cycles,confirming its great application potential in sodiumbased storage devices.

关键词： Vanadium disulfide Reduced graphene oxide Anode Sodium-ion battery Sodium-ion capacitor

Comparison of biliary protein spectrum in gallstone patients with obesity and those with normal body weight

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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 385-392页

作者： Min-zhi Chen Ping xie Xiao-Chang Wu Zhen-Hua Tan Hai Qian zhi-Hong Ma Xing Yao Department of Hepatopancreatobiliary Surgery Huzhou Central HospitalAffiliated Huzhou HospitalZhejiang University School of MedicineHuzhou 313000China Huzhou Key Laboratory of Molecular Medicine Huzhou Central HospitalAffiliated Huzhou HospitalZhejiang University School of MedicineHuzhou 313000China

Background:Obesity is a common public health issue and is currently deemed a disease.Research has shown that the risk of gallstones in individuals with obesity is elevated.This study aimed to explore the bile proteomics differences between cholelithiasis patients with obesity and normal body weight.Methods:Bile samples from 20 patients(10 with obesity and 10 with normal body weight)who underwent laparoscopic cholecystectomy at our center were subjected to tandem mass tag labeling(TMT)and liquid chromatography-tandem mass spectrometry(LC-MS/MS),followed by further bioinformatic analysis.Results:Among the differentially expressed proteins,23 were upregulated and 67 were downregulated.Bioinformatic analysis indicated that these differentially expressed proteins were mainly involved in cell development,inflammatory responses,glycerolipid metabolic processes,and protein activation cascades.In addition,the activity of the peroxisome proliferator-activated receptor(PPAR,a subfamily of nuclear receptors)signaling pathway was decreased in the Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis.Two downregulated proteins in the PPAR signaling pathway,APO A-I and APO A-II,were confirmed using enzyme-linked immunosorbent assay.Conclusions:The PPAR signaling pathway may play a crucial role in the development of cholelithiasis among patients with obesity.Furthermore,biliary proteomics profiling of gallstones patients with obesity is revealed,providing a reference for future research.

关键词： Proteome profiling Gallstones Obesity-associated gallstones Tandem mass tag labeling PPAR signaling

Secular trends of asthma mortality in China and the United States from 1990 to 2019

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Chinese Medical Journal 2024年第3期137卷 273-282页

作者： Xiaochen Li Mingzhou guo Yang Niu Min xie Xiansheng Liu Department of Pulmonary and Critical Care Medicine Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430030China NHC Key Laboratory of Respiratory Diseases WuhanHubei 430030China

Background:Asthma imposes a large healthcare burden in China and the United States(US).However,the trends of asthma mortality and the relative risk factors have not been comparatively analyzed between the countries.The aim of this study was to compare the mortality and risk factors between China and the US.Methods:The deaths,and mortality rates of asthma in China and the US during 1990–2019 were obtained from the Global Burden of Disease Study 2019.The age–period–cohort model was used to estimate these mortality rates based on a log-linear scale with additive age,period,and cohort effects.The population attributable fractions of risk factors for asthma were estimated.Results:In 1990–2019,the asthma mortality rate was higher in China than in the US.The crude and age-standardized asthma mortality rates trended downward in both China and the US from 1990 to 2019.The decline in mortality was more obvious in China.Mortality gap between the two countries was narrowing.A sex difference in asthma mortality was observed with higher mortality in males in China and females in the US.The age effects showed that mortality increased with age in adults older than 20 years,particularly in the elderly.Downward trends were generally observed in the period and cohort rate ratios in both countries,with China experiencing a more obvious decrease.Smoking and high body mass index(BMI)were the leading risk factors for asthma mortality in China and the US,respectively.Mortality attributable to occupational asthmagens and smoking decreased the most in China and the US,respectively.Conclusions:In 1990–2019,the asthma mortality rate was higher in China than in the US;however,the mortality gap has narrowed.Mortality increased with age in adults.The improvements in asthma death risk with period and birth cohort were more obvious in China than in the US.Smoking,high BMI,and aging are major health problems associated with asthma control.The role of occupational asthmagens in asthma mortality underscores the importance of management and preventi

关键词： Asthma Mortality Global disease burden China the United States Age–period–cohort model