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Photochemical oxidation of dimethylsulfide in seawater

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Acta Oceanologica Sinica 2007年第5期26卷 34-42页

作者： YANG Guipeng LI Chengxuan QI jialin HU Lige hou Haijun Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education Ocean University of China Qingdao 266100 China

Dimethylsulfide （DMS） is generally thought to be lost from the surface oceans by evasion into the atmosphere as well as consumption by microbe. However, photochemical process might be important in the removal of DMS in the oceanic photic zone. A kinetic investigation into the photochemical oxidation of DMS in seawater was performed. The photo-oxidation rates of DMS were influenced by various factors including the medium, dissolved oxygen, photosensitizers, and heavy metal ions. The photo-oxidation rates of DMS were higher in seawater than in distilled water, presumably due to the effect of salinity existing in seawater. Three usual photosensitizers （humic acid, fulvic acid and anthroquinone）, especially in the presence of oxygen, were able to enhance the photo-oxidation rate of DMS, with the fastest rate observed with anthroquinone. Photo-oxidation of DMS followed first order reaction kinetics with the rate constant ranging from 2.5 × 10^-5 to 34.3 × 10^-5. Quantitative analysis showed that approximately 32% of the photochemically removed DMS was converted to dimethylsulfoxide. One of the important findings was that the presence of Hg^2 ＋ could markedly accelerate the photo-oxidation rate of DMS in seawater. The mechanism of mercuric catalysis for DMS photolysis was suggested according to the way of CTTM （ charge transfer to metal） of DMS - Hg^2＋ complex.

关键词： dimethylsulfide photochemistry kinetics metal ion seawater

Design and test of the plant-correcting reel for harvesting lodging garlic plants

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 59-68页

作者： Yuhua Li Chao Li Lupeng Liu Kai Zhou jialin hou College of Mechanical and Electronic Engineering Shandong Agricultural UniversityTai’an 271018ShandongChina College of Biosystems Engineering&Food Science Zhejiang UniversityHangzhou 310058China

Crops are prone to lodging with the decline of stem moisture and the intervention of other factors in the mature harvest period,such as garlic,which is difficult to harvest *** solve this problem,the plant-correcting reel for harvesting lodging garlic plants,bumped and deformed with plants many times to pull and lift them into a conveyor,is proposed in this *** analyzed the motion trajectory equation and key influencing factors of the reel and defined the lifting and plant-correcting stages as three processes of contact,stirring and *** example,the contact deformation model and system energy equations were established in the contact ***,in the stirring process,the garlic plant-correcting conditions were established through the dynamic simulation test analysis of garlic seedling trajectories and the deflection model of garlic stem was ***,in the release process,the expressions of rubber bars rotation and garlic plant offset bending curvature were constructed and the optimal number and distribution form of bars were ***,the mechanism and key operating parameters of the auxiliary lifting mechanism of the divider were *** the single-factor test,the influence of reel speed,forward speed and reel height on the success feeding rate was analyzed under different bars distribution forms;Through multi-factor experiments,the interaction contour map of various factors was *** reel speed,forward speed and reel height were 3 rad/s,3.5 m/s,and 540 mm,the feeding success rate was 98.73%.The optimization factors were tested and verified,which met the operational requirements of a high feeding success rate and low loss rate of garlic *** study combines laboratory virtual as well as field experiments and analyzes of trajectory of bars,contact deformation and deflection model of garlic plant,and reel rotation and garlic plant offset bending curvature to solve the problem of ga

关键词： feeding success rate lodging garlic harvesting reel plant model field test

Design and experiment of automatic garlic seed directing device

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International Journal of Agricultural and Biological Engineering 2020年第6期13卷 85-93页

作者： Aijun Geng Xiaoyu Li jialin hou Ji Zhang Zhilong Zhang Jun Chong College of Mechanical and Electrical Engineering Shandong Agricultural UniversityTaian 271018ShandongChina Shandong Key Laboratory of Horticultural Machinery and Equipment Taian 271018ShandongChina Ji'nan Huaqing Agricultural Machinery Technology Co. Ltd.Ji'nan 251600ShandongChina

Garlic planting requires a single seed with a scaly bud upward and *** this study,an automatic garlic seed directing device was designed for auxiliary garlic seeding by utilizing a seed placed funnel,a correcting mechanism,and an automatic control *** factors influenced device performance:characteristics of garlic seeds,limited notch diameter of the seed placed funnel,and funnel taper of the seed placed *** most optimal structural parameters of the seed placed funnel were determined via theoretical *** research samples of Lanling and Jinxiang garlic were divided into three groups according to their respective sizes.3D design software(Solidworks)was used to simulate the above three factors and analyze their rules of *** obtained simulation results demonstrated that the suitable range of funnel taper and limited notch diameter of seed placed funnel for the three groups of seed were from 40°to 60°and 6-8 mm,*** bench test showed that when the funnel taper was 60°and the limited notch diameter was 10 mm,the success rates of the three groups’seeds in terms of scaly bud directing were 89.8%,91.6%and 96.6%respectively,which satisfied the agricultural requirements of garlic ***,the corresponding results may promote the study and improvement of garlic intelligent planting equipment.

关键词： garlic garlic seed directing simulation and analysis automatic control

Expanding Asgard members in the domain of Archaea sheds new light on the origin of eukaryotes

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Science China(Life Sciences) 2022年第4期65卷 818-829页

作者： Ruize Xie Yinzhao Wang Danyue Huang jialin hou Liuyang Li Haining Hu Xiaoxiao Zhao Fengping Wang School of Oceanography Shanghai Jiao Tong UniversityShanghai200030China State Key Laboratory of Microbial Metabolism School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai200240China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519082China

The hypothesis that eukaryotes originated from within the domain Archaea has been strongly supported by recent phylogenomic analyses placing Heimdallarchaeota-Wukongarchaeota branch from the Asgard superphylum as the closest known archaeal sister-group to eukaryotes. However, our understanding is still limited in terms of the relationship between eukaryotes and archaea, as well as the evolution and ecological functions of the Asgard archaea. Here, we describe three previously unknown phylum-level Asgard archaeal lineages, tentatively named Sigyn-, Freyr-and Njordarchaeota. Additional members in Wukongarchaeota and Baldrarchaeota from distinct environments are also reported here, further expanding their ecological roles and metabolic capacities. Comprehensive phylogenomic analyses further supported the origin of eukaryotes within Asgard archaea and a new lineage Njordarchaeota was supposed as the known closest branch with the eukaryotic nuclear host lineage. Metabolic reconstruction suggests that Njordarchaeota may have a heterotrophic lifestyle with capability of peptides and amino acids utilization, while Sigynarchaeota and Freyrarchaeota also have the potentials to fix inorganic carbon via the Wood-Ljungdahl pathway and degrade organic matters. Additionally, the Ack/Pta pathway for homoacetogenesis and de novo anaerobic cobalamin biosynthesis pathway were found in Freyrarchaeota and Wukongrarchaeota,respectively. Some previously unidentified eukaryotic signature proteins for intracellular membrane trafficking system, and the homologue of mu/sigma subunit of adaptor protein complex, were identified in Freyrarchaeota. This study expands the Asgard superphylum, sheds new light on the evolution of eukaryotes and improves our understanding of ecological functions of the Asgard archaea.

关键词： Asgard archaea eukaryotic origin metagenome

Geometrical design of variable ratio tooth profile based on Boolean subtraction operation and a novel modification method

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International Journal of Agricultural and Biological Engineering 2020年第5期13卷 125-133页

作者： Ziru Niu Jianlei Li Shuai Xin Liangliang Zou Yuhua Li jialin hou Ming Tu Ting Sun College of Mechanical and Electronic Engineering Shandong Agricultural UniversityTai’an 271018ShandongChina Shandong Provincial Key Laboratory of Horticultural Machinery and Equipment Tai’an 271018ShandongChina College of Engineering Huazhong Agricultural UniversityWuhan 430070China Key Laboratory of Agricultural Equipment in Mid-lower Reaches of the Yangtze River Ministry of Agriculture and Rural AffairsWuhan 430070China Shandong Huasheng Pesticide Machinery Co. LtdLinyi 276017ShandongChina

Variable transmission ratio racks show great potential in rice transplanters as a key component of variable transmission ratio steering to balance steering portability and *** objective of this study was to develop a novel geometrical design method to achieve quick,high-quality modeling of the free curvilinear tooth profile of a variable transmission ratio ***,a discrete envelope motion 3D model was established between the pinion-sector and the variable transmission ratio rack blank based on the mapping relationship between the rotation angle of the pinion-sector and the displacement of the rack,according to the variable transmission ratio *** on the loop Boolean subtraction operation,which removed the pinion-sector from the rack blank during all moments of the discrete motion process,the final complex changing tooth shape of the variable transmission ratio rack was ***,since Boolean cutting residues made the variable ratio tooth surface fluctuant and eventually affected the precision of the model,this study proposed a modification method for establishing a smooth and continuous tooth ***,a novel fitting algorithm used approximate variable ratio tooth profile points extracted from the Boolean cutting marks and generated a series of variable ratio tooth profiles by utilizing B-spline with different ***,based on a transmission stability simulation,the variable ratio tooth profile with optimal dynamic performance was selected as the final ***,tests contrasting the transmission stability of the machining samples of the initial variable ratio tooth profile and the final variable ratio tooth profile were *** results indicated that the final variable ratio tooth profile is more effective than the initial variable ratio tooth ***,the proposed variable ratio tooth profile modeling and modification method for eliminating Boolean cutting residues and improving surface accuracy is prov

关键词： rice transplanter steering variable ratio tooth profile variable ratio curve Boolean subtraction operation transmission stability

Design and test of a dual-axis layered rotary tillage stubble exterminator in saline-alkali land based on discrete elements

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International Journal of Agricultural and Biological Engineering 2024年第5期17卷 163-175页

作者： Zhuang Zhao Dongwei Wang Shuqi Shang Peng Guo Zenghui Gao Chao Xia Haipeng Yan jialin hou College of Mechanical and Electronic Engineering Shandong Agricultural UniversityTai’an 271018ShandongChina College of Mechanical and Electrical Engineering Qingdao Agricultural UniversityQingdao 266109ShandongChina Yellow River Delta Intelligent Agricultural Machinery Equipment Industry Research Institute Document Dongying 257300ShandongChina College of Mechanical and Electronic Engineering Xinjiang Agricultural UniversityUrumqi 830052China

Considering the problems of poor straw mulching performance,low soil crushing rate and poor straw mulching performance of the traditional rotary tiller on saline-alkali soils,a two-axis layered rotary stubble cutter for saline-alkali soils with front-axis positive rotation of the front axle and rear-axis counter-rotation of the rear axle was developed,focusing on the kinetic properties of the straw and soil under positive and *** addition,the most important structural parameters and the arrangement of the front-axis stubble cutting knife and the rear-axis return knife were analyzed and ***-Mindlin with bonding was used to create a discrete element model of the agglomerate of implement,straw and *** forward speed,horizontal distance and vertical distance were used as test factors,and the straw return rate and soil fragmentation rate were used as test indexes to analyze the straw-soil transport law under different operating parameters from a microscopic point of view,and then Design-Expert was used to conduct the test 1.07 km/h,horizontal distance of 569.55 mm,vertical distance of 176.59 *** validate the performance of the two-axis,layered rotary tiller,a field trial was conducted and the results show that the straw return ratio was(91.59±0.41)%,soil fragmentation ratio was(91.90±0.29)%and tillage depth stability was(91.52±0.46)%,which met the requirements for peanut seedbed preparation on saline-alkali land.

关键词： saline-alkali land straw return soil fragmentation dual-axis layering discrete element simulation field trial

Design and Optimization of Planting Process Parameters for 2ZYX-2 Type Green Onion Ditching and Transplanting Machine

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Phyton-International Journal of Experimental Botany 2020年第1期89卷 147-166页

作者： Jiqiang Zhang Ziru Niu Tianhua Li Yanqiang Wu Rui Xi Yuhua Li Guanghua Li jialin hou College of Mechanical and Electronic Engineering Shandong Agricultural UniversityTai’an271018China College of Horticultural Science and Engineering Shandong Agricultural UniversityTai’an271018China Qingzhou Hualong Machinery Technology Development Co. Ltd.Qingzhou262500China

Considering the current low level of mechanization for domestic green onion planting and the high labor intensity of artificial planting,a 2ZYX-2 green onion ditching and transplanting machine,which can complete ditching,ridging,transplanting,repression,soil covering and other operations,is designed in this *** Central Composite test design method was carried out with the speed of the transplanting machine,the depth of the opener and the horizontal position of the opener as the experimental factors and with the qualification ratio of perpendicularity,the variation coefficient of the plant spacing and the qualification ratio of the planting depth as the test *** the analysis of the model interaction and response surface,the change laws that the influence the machine’s forward speed,the depth of the opener and the horizontal position of the opener were *** regression model was optimized by Design-Expert 8.0.6 software,and the accuracy of the predicted results was verified by *** optimal working parameters showed that the forward speed of the machine was 0.06 m/s,the depth of the opener was 102 mm,and the horizontal position of the opener was 29 *** conditions of optimal working parameters,the qualification rate of the verticality was 86.83%,the coefficient of variation for the plant spacing was 2.77,and the pass rate of planting depth was 88.26%.The research related to the thesis can provide a reference for the mechanized planting of green onion,which is of great significance to the cost-effectiveness of the green onion industry.

关键词： Agricultural machinery motion analysis green onion experiment

Widespread Bathyarchaeia encode a novel methyltransferase utilizing lignin-derived aromatics

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mLife 2023年第3期2卷 272-282页

作者： Tiantian Yu Haining Hu Xianhong Zeng Yinzhao Wang Donald Pan Longhui Deng Lewen Liang jialin hou Fengping Wang School of Oceanography Shanghai Jiao Tong UniversityShanghaiChina State Key Laboratory of Microbial Metabolism School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)ZhuhaiChina

Lignin degradation is a major process in the global carbon cycle across both terrestrial and marine ***,which are among the most abundant microorganisms in marine sediment,have been proposed to mediate anaerobic lignin ***,the mechanism of bathyarchaeial lignin degradation remains ***,we report an enrichment culture of Bathy-archaeia,named Candidatus Baizosediminiarchaeum ligniniphilus DL1YTT001(***),from coastal sediments that can grow with lignin as the sole organic carbon source under mesophilic anoxic *** possesses and highly expresses novel methyltransferase 1(MT1,mtgB)for transferring methoxyl groups from lignin monomers to cob(I)*** have no homology with known microbial methyltransferases and are present only in bathyarchaeial *** expression of the mtgB gene confirmed O-demethylation *** mtgB genes were identified in metagenomic data sets from a wide range of coastal sediments,and they were highly expressed in coastal sediments from the East China *** findings suggest that Bathyarchaeia,capable of O-demethylation via their novel and specific methyltransferases,are ubiquitous in coastal sediments.

关键词： Bathyarchaeia coastal sediments lignin-degrading lignin-derived aromatics specific methyltransferase

Design and Test of the Semi-Automatic Test-Bed with Inclined Belt of Garlic Transplanting Machine

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American Journal of Plant Sciences 2015年第19期6卷 3298-3305页

作者： Zhaolei Zhang Aijun Geng Jianning Yang Ruxin Li jialin hou Shandong Changlin Deutz-Fahr Machinery Ltd. Linyi China Mechanical and Electrical Engineering College Shandong Agriculture University Tai’an China Shandong Provincial Key Laboratory of Horticultural Machineries and Equipments Tai’an China

In order to verify the feasibility of semi-automatic garlic planter with inclined belt program and determine its reasonable operating parameters, the semi-automatic test-bed with inclined belt of garlic transplanting machine was designed, and the garlic box experiments were conducted. The angle of inclined belt on the test-bed and its running speed were adjustable. Single factor test results showed that the program of the semi-automatic garlic planter with inclined belt was feasible, and the angle of inclined belt and the test bed running speed affected the indicators. Orthogonal experiment results showed that the angle of inclined belt was the main factor affecting the test indicators. It is also found that the best angle was 30 degrees, while the most reasonable running speed was 0.75 Km/h.

关键词： Garlic Planter Inclined Belt Test-Bed