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Design and test of the key components for a combing-type tobacco harvester

International Journal of Agricultural and Biological Engineering 2024年第1期17卷 145-153页

作者： Chaoran Sun Shaohui tan Songling Sun Mingtao Xiao limei Chen Wenke Ai Zhihua Qiu Ping Jiang Yang He School of Mechanical and Electrical Engineering Hunan Agricultural UniversityChangsha 410128China Truking Technology Limited Ningxiang 410600HunanChina Construction of tobacco leaf production infrastructure of Hunan Province Company of China National Tobacco Corporation office Changsha 410009China

In response to the problems of low efficiency,high labor intensity,and low mechanization in manual tobacco harvesting,a comb-off tobacco picking device for southern hilly tobacco areas was designed following the agronomic requirements and the principle of manual picking of tobacco harvesting in southern China.The device was composed of the power chassis,picking mechanism,and storage mechanism.This study involved the theoretical analysis,structural design,and modeling of the key components,such as chassis structure,combing-type picking mechanism,and power synchronization mechanism.The results of the motion analysis and calculation of the picking process demonstrated that the adjustment range of the comb chain elevation angles was from 12.4°to 20.9°,the comb rod installation distance was 76.2 mm,and the synchronizing mechanism transmission ratio was 3:10.One-factor test and three-factor three-level orthogonal test was performed with the forward speed of the chassis,the distance between the picking device baffles and the elevation angle of the chain with the combing bar as test factors,and the rate of broken and missed tobacco picking as evaluation indicators.It was revealed that the optimal combination of the forward speed of the chassis,the distance between the baffles,and the chain elevation angle were 1.5 km/h,75 mm,and 12.4°,respectively.Moreover,verification tests suggested that the breakage rate of tobacco leaves was 9.99%,and the probability of missed tobacco picking was 7.31%,both of which satisfy the agriculture requirements and the operational requirements in the agricultural machinery certification syllabus.

关键词： harvesting machinery leaf tobacco combing-type tiered harvest synchronizing mechanism

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Numerical manifold method for steady-state nonlinear heat conduction using Kirchhoff transformation

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Science China(Technological Sciences) 2024年第4期67卷 992-1006页

作者： ZHANG limei KONG Heng ZHENG Hong Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing 100124China Beijing Municipal Construction Co. Ltd.Beijing 100048China

The numerical manifold method(NMM)introduces the mathematical and physical cover to solve both continuum and discontinuum problems in a unified manner.In this study,the NMM for solving steady-state nonlinear heat conduction problems is presented,and heat conduction problems consider both convection and radiation boundary conditions.First,the nonlinear governing equation of thermal conductivity,which is dependent on temperature,is transformed into the Laplace equation by introducing the Kirchhoff transformation.The transformation reserves linearity of both the Dirichlet and the Neumann boundary conditions,but the Robin and radiation boundary conditions remain nonlinear.Second,the NMM is employed to solve the Laplace equation using a simple iteration procedure because the nonlinearity focuses on parts of the problem domain boundaries.Finally,the temperature field is retrieved through the inverse Kirchhoff transformation.Typical examples are analyzed,demonstrating the advantages of the Kirchhoff transformation over the direct solution of nonlinear equations using the NewtonRaphson method.This study provides a new method for calculating nonlinear heat conduction.

关键词： numerical manifold method nonlinear heat conduction temperature-dependent thermal conductivity Kirchhoff transformation convection and radiation boundary conditions

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Targeted therapeutic effects of oral magnetically driven pectin nanoparticles containing chlorogenic acid on colon cancer

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Particuology 2024年第1期84卷 53-59页

作者： Huatai Zhu limei Zhang Fujia Kou Jingyang Zhao Jiandu Lei Jing He Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityBeijing100083China Institute of Biopharmaceutical and Health Engineering Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen518055China

Oral colonic nano-drug delivery system has attracted growing attention in treating colon cancer for their excellent characteristics.However,the unique and complex structure of the gastrointestinal tract is still an obstacle to the safe delivery of drugs targeting sites in colon tumors.Here,we designed magnetically driven dual-targeted oral colonic nanoparticles loaded with chlorogenic acid using pectin and oleic acid-modified iron oxide(Fe3O4@OA).Specific degradation of pectin by pectinase produced by colonic flora and magnetic fields applied to the colon confers specific targeting of nanoparticles to the colon.In order to overcome the challenge of preparing magnetically driven nanoparticles with small and homogeneous particle sizes by a single conventional method,we developed the combined ultrasound-emulsification technique.The average particle size of the prepared nanoparticles was 81.04±1.02 nm,which showed good drug release in the simulated colonic environment.In vitro anticancer studies,the drug-loaded nanoparticles possess an obvious toxicity and apoptosis-inducing ability against cancer cells.Meanwhile,the hemolysis results demonstrated the safety of the nanoplatform(PET/CGA/Fe_(3)O_(4)@OA).This work holds broad prospects as a new treatment modality for colon cancer.

关键词： Pectin Chlorogenic acid Ultrasound-emulsion Magnetically driven Colon cancer Colon targeted

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Environmental benefits and farmers' adoption of winter cover crops in the North China Plain

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Pedosphere 2024年第1期34卷 159-169页

作者： Shufang GUO Yitao ZHANG limei ZHAI Jian LIU Hongyuan WANG Hongbin LIU State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China Key Laboratory of Nonpoint Source Pollution ControlMinistry of Agriculture and Rural AffairsInstitute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China Institute of Agricultural Environment and Resources Yunnan Academy of Agricultural SciencesKunming 650205China Shandong Yucheng Agro-ecosystem National Observation Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China The Norwegian Institute of Bioeconomy Research(NIBIO) Akershus 1431Norway

The introduction of cover crops into monoculture systems to improve soil health has been widely adopted worldwide. However, little is known about the environmental risks and application prospects of different cover crops in spring maize(Zea mays L.) monocultures proposed in the North China Plain. A pot experiment was conducted to evaluate the effects of different winter cover crops on subsequent maize yield, soil fertility, and environmental risks of nitrogen(N) loss, and a questionnaire survey was conducted to examine factors influencing farmers' willingness to adopt cover crops in the North China Plain. Based on the same fertilization regime during the maize growing period, four winter cover crop treatments were set up, including bare fallow, hairy vetch(Vicia villosa Roth.), February orchid(Orychophragmus violaceus), and winter oilseed rape(Brassica campestris L.). The results indicated that winter cover crops significantly increased subsequent maize yield and soil organic carbon, total N, and microbial biomass carbon and N compared with the bare fallow treatment.The incorporation of cover crops led to a negligible increase in nitrous oxide(N_(2)O) emissions and had a very limited effect on ammonia(NH_(3)) emissions.The incorporation of February orchid and winter oilseed rape decreased nitrate leaching compared with the hairy vetch treatment in the maize growing season.The N losses via N_(2)O and NH_(3) emissions and N leaching accounted for 71%–84% of the N surplus. However, yield increase and environmental benefits were not the main positive factors for farmers to accept cover crops. Financial incentive was rated by 83.9% of farmers as an “extremely important” factor, followed by other costs, when considering winter cover cropping. These results indicate that the environmental benefits depend on the type of cover crop. Maintaining high levels of soil fertility and maize yield, providing sufficient subsidies, and encouraging large-area cultivation of cover crops are critical measures to promote winter cover c

关键词： cover crop N leaching NH_(3)emission N_(2)O emission spring maize willingness to accept

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Metagenomics analysis identifies oral Streptococcus as potential biomarkers for nasopharyngeal carcinoma

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Journal of Genetics and Genomics 2024年第3期51卷 363-366页

作者： Yanmin Liu Chengtao Wang Lixiang Xie Shuling Du Li Ding Ying Cui Runzhi Chen Jingxiang Zhang Wan Wang Xi Liu Yan Wang Shiyan Chen Tian tan Qiaochu Zhao limei Yin Chunwei Li Yong Chen Tao Ding Department of Immunology and Microbiology Zhongshan School of MedicineSun Yat-sen UniversityGuangzhouGuangdong 510080China Key Laboratory of Tropical Disease Control(Sun Yat-sen University) Ministry of EducationGuangzhouGuangdong 510080China Department of Radiation Oncology The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong 510080China Department of Infectious Diseases The Fifth Affiliated HospitalSun Yat-sen UniversityZhuhaiGuangdong 519000China Department of Endocrinology&Metabolism The Fifth Affiliated HospitalSun Yat-sen UniversityZhuhaiGuangdong 519000China Department of Otolaryngology The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong 510080China

Nasopharyngeal carcinoma(NPC)is a malignancy originating from the nasopharyngeal epithelial cells.Although some studies have identified potential biomarkers for early diagnosis of NPC based on metabolomics data(Chen et al.,2023;Zhou et al.,2023)and Epstein-Barr virus subtypes(Xu et al.,2019),their effectiveness and applicability need further investigation,particularly when consideringthe roles of oral microbiota.

关键词： al. nasopharyngeal diagnosis

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Review on the effect of isomorphic replacement on the structure and application performance of typical clay minerals

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Progress in Natural Science:Materials International 2024年第2期34卷 251-262页

作者： Ritong Huang limei Wu Xiaolong Wang Ning tang Lili Gao Aiqin Wang Yushen Lu School of Materials Science and Engineering Shenyang Jianzhu University School of Mechanical Engineering Shenyang Jianzhu University Key Laboratory of Clay Mineral Applied Research of Gansu Province Center of Eco-material and Green Chemistry Lanzhou Institute of Chemical Physics Chinese Academy of Sciences

Clay minerals represent a class of hydrated phyllosilicates making up the fine-grained portions of rocks, sediments, and soils. Due to the advantages of abundant reserves, low prices, and wide applications, the development and utilization of clay minerals have received increasing attention in recent years. Isomorphic replacement is a common phenomenon in clay minerals, which is one of the main causes of changes in mineral chemical composition and physical and chemical properties. This article briefly describes the crystal structure of several clay minerals such as montmorillonite, vermiculite, palygorskite, kaolinite, and halloysite. It summarized the research status of the effect of isomorphic replacement on their structure and application performance. The research results can provide theoretical basis for the structural research and efficient resource utilization of clay minerals.

关键词： Clay minerals Crystal structure Isomorphism Application performance

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Hemoperfusion and continuous veno-venous hemodiafiltration for eliminating chlorfenapyr in poisoning patients

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World Journal of Emergency Medicine 2024年第3期15卷 235-237页

作者： Yanqing Liu Xiaoxia Lu Haochun Wang Ming Niu Renzheng Zhang Zhongying Liu limei Han Xiaobo Peng Xigang Zhang Poisoning Treatment Department Senior Department of Hematologythe Fifth Medical Center of PLA General HospitalBeijing 100039China

Chlorfenapyr is a liposoluble insecticide belonging to the pyrrole family.Chlorfenapyr is activated when the N-ethoxymethyl side chain breaks,forming a toxic metabolite,which uncouples oxidative phosphorylation in the mitochondria,inhibits the production of adenosine triphosphate (ATP),and leads to the death of cells and targe organisms.[1] Symptoms of chlorfenapyr poisoning in patients are mild and atypical in the early stage,especially in patients receiving low dose exposure;however,such cases are rare and may be ignored by physicians,often leading to delayed treatment.[2,3].

关键词： patients perfusion eliminating

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Environmental,economic and exergy analysis of separation of ternary azeotrope by variable pressure extractive distillation based on multi-objective optimization

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Chinese Journal of Chemical Engineering 2024年第1期65卷 145-157页

作者： Peizhe Cui Jiafu Xing Chen Li Mengjin Zhou Jifu Zhang Yasen Dai limei Zhong Yinglong Wang College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China

In this work,the ternary azeotrope of tert-butyl alcohol/ethyl acetate/water is separated by extractive distillation(ED)to recover the available constituents and protect the environment.Based on the conductor like shielding model and relative volatility method,ethylene glycol was selected as the extractant in the separation process.In addition,in view of the characteristic that the relative volatility between components changes with pressure,the multi-objective optimization method based on nondominated sorting genetic algorithm II optimizes the pressure and the amount of solvent cooperatively to avoid falling into the optimal local solution.Based on the optimal process parameters,the proposed heat-integrated process can reduce the gas emissions by 29.30%.The heat-integrated ED,further coupled with the pervaporation process,can reduce gas emission by 42.36%and has the highest exergy efficiency of 47.56%.In addition,based on the heat-integrated process,the proposed two heat pump assisted heat-integrated ED processes show good economic and environmental performance.The double heat pump assisted heat-integrated ED can reduce the total annual cost by 28.78%and the gas emissions by 55.83%compared with the basis process,which has a good application prospect.This work provides a feasible approach for the separation of ternary azeotropes.

关键词： Extractive distillation Optimization Mixtures Separation

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Influence of ambient temperature on the CO_(2)emitted of light-duty vehicle

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Journal of Environmental Sciences 2024年第6期140卷 59-68页

作者： Dan tan Yachao Wang Jianwei tan Jiachen Li Changyu Wang Yunshan Ge School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China

Because of global warming,people have paid more attention to greenhouse gas emitted by vehicles.To quantify the impact of temperature on vehicle CO_(2)emissions,this study was conducted using the world light vehicle test cycle on two light-duty E10 gasoline vehicles a ambient temperatures of-10,0,23,and 40℃,and found that CO_(2)emission factors of Vehicle1 in the low-speed phase were 22.07%and 20.22%higher than those of Vehicle 2 at cold star and hot start under-10℃.The reason was vehicle 1 had a larger displacement and more friction pairs than vehicle 2.There was the highest CO_(2)emission at the low-speed phase due to low average speed,frequent acceleration,and deceleration.The CO_(2)temperature factor and the ambient temperature had a strong linear correlation(R2=0.99).According to CO_(2)temperature factors and their relationships,CO_(2)emission factors of other ambien temperatures could be calculated when the CO_(2)emission factor of 23℃was obtained,and the method also could be used to obtain the CO_(2)temperature factors of different vehicles.To separate the effect of load setting and temperature variation on CO_(2)emission quantitatively a method was proposed.And results showed that the load setting was dominant for the CO_(2)emission variation.Compared with 23℃,the CO_(2)emission for vehicle 1 caused by load setting variation were 62.83 and 47.42 g/km,respectively at-10 and 0℃,while those fo vehicle 2 were 45.01 and 35.63 g/km,respectively.

关键词： CO_(2)emission Ambient temperature E10 gasoline Light-duty vehicle WLTC

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Genetic and lipidomic analyses reveal the key role of lipid metabolism for cold tolerance in maize

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Journal of Genetics and Genomics 2024年第3期51卷 326-337页

作者： Lei Gao Haifang Jiang Minze Li Danfeng Wang Hongtao Xiang Rong Zeng limei Chen Xiaoyan Zhang Jianru Zuo Shuhua Yang Yiting Shi State Key Laboratory of Plant Environmental Resilience College of Biological SciencesFrontiers Science Center for Molecular Design BreedingCenter for Crop Functional Genomics and Molecular BreedingChina Agricultural UniversityBeijing 100193China State Key Laboratory of Wheat&Maize Crop Science College of Life SciencesHenan Agricultural UniversityZhengzhouHenan 450002China State Key Laboratory of Plant Genomics Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Suihua Branch of Heilongjiang Academy of Agricultural Machinery Sciences SuihuaHeilongjiang 152052China

Lipid remodeling is crucial for cold tolerance in plants.However,the precise alternations of lipidomics during cold responses remain elusive,especially in maize(Zea mays L.).In addition,the key genes responsible for cold tolerance in maize lipid metabolism have not been identified.Here,we integrate lipidomic,transcriptomic,and genetic analysis to determine the profile of lipid remodeling caused by cold stress.We find that the homeostasis of cellular lipid metabolism is essential for maintaining cold tolerance of maize.Also,we detect 210 lipid species belonging to 13 major classes,covering phospholipids,glycerides,glycolipids,and free fatty acids.Various lipid metabolites undergo specific and selective alterations in response to cold stress,especially mono-/di-unsaturated lysophosphatidic acid,lysophosphatidylcholine,phosphatidylcholine,and phosphatidylinositol,as well as polyunsaturated phosphatidic acid,monogalactosyldiacylglycerol,diacylglycerol,and triacylglycerol.In addition,we identify a subset of key enzymes,including ketoacyl-acyl-carrier protein synthase II(KAS II),acyl-carrier protein 2(ACP2),male sterility33(Ms33),and stearoyl-acyl-carrier protein desaturase 2(SAD2)involved in glycerolipid biosynthetic pathways are positive regulators of maize cold tolerance.These results reveal a comprehensive lipidomic profile during the cold response of maize and provide genetic resources for enhancing cold tolerance in crops.

关键词： Maize Cold stress Lipid metabolism Transcriptome Lipidomic

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