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Design and experiment of a Chinese chive harvester

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International Journal of Agricultural and Biological Engineering 2023年第2期16卷 125-131页

作者： Yulong FENG Xuchao Yin Hairong Jin Wenyu Tong Xiaofeng Ning College of Engineering Shenyang Agricultural UniversityShenyang 110866China Key Laboratory of Modern Horticultural Equipment Ministry of Agriculture and Rural AffairsShenyang 110866China

Recognizing the labor intensity of current domestic Chinese chive harvesting and the need for its mechanized harvesting,a self-propelled electric Chinese chive harvester is designed.The machine is composed of a control system,supporting mechanism,cutting parts,conveying and clamping mechanisms,frame,and collection system.It can complete Chinese chive feeding,cutting,transmission,and binning operations at one time.It has a cutting width of 0.25 m and wheelbases of 260 mm and 460 mm.Two 12 V,42 Ah lead-acid batteries were used in series as the power supply.The mechanical properties of Chinese chive were analyzed,and shear and compression tests were carried out to determine that the average value of the maximum shear force on the chives is 129 N.Up to a compressive force of 225 N,Chinese chives are not damaged.According to the physical characteristics of Chinese chives and the requirements of the harvesting operations,design and calculation of the key components of the harvester’s transmission mechanism and the strength of the whole machine frame were completed.An embedded control system and Cortex-M3 microprocessor were used to control the harvester and realize its functions of rolling and harvesting while regulating its speed and protecting its motor.Using the Box-Behnken test design method,the machine’s operating speed,cutter speed,and cutter height were selected as influencing factors,and the lodging rate and loss rate were evaluated as a test.A mathematical regression model of influencing factors and evaluation indexes was established to analyze the influence of these factors and indexes and optimize test parameters.The optimal parameter combination is determined to be:operating speed,1.1 km/h;cutter speed,220 r/min;cutter height 2.0 cm.The parameters were verified from field tests and the results showed that under the optimized parameter combination,the average lodging rate was 3.96% and the average loss rate was 3.23%,indicating that the Chinese chive harvester meets the agronomic requirements of Chinese chiv

关键词： harvester clamping mechanism test design lodging rate Chinese chive

Flexural behavior of high-strength,steel-reinforced,and prestressed concrete beams

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Frontiers of Structural and Civil Engineering 2021年第1期15卷 227-243页

作者： Qing JIANG Hanqin WANG Xun CHONG Yulong FENG Xianguo YE School of Civil and Hydraulic Engineering Hefei University of TechnologyHefei 230009China Anhui Key Laboratory of Civil Engineering and Materials Hefei 230009China College of Water Conservancy and Civil Engineering Xinjiang Agricultural UniversityUrumqi 830052China

To study the flexural behavior of prestressed concrete beams with high-strength steel reinforcement and high-strength concrete and improve the crack width calculation method for flexural components with such reinforcement and concrete,12 specimens were tested under static loading.The failure modes,flexural strength,ductility,and crack width of the specimens were analyzed.The results show that the failure mode of the test beams was similar to that of the beams with normal reinforced concrete.A brittle failure did not occur in the specimens.To further understand the working mechanism,the results of other experimental studies were collected and discussed.The results show that the normalized reinforcement ratio has a greater effect on the ductility than the concrete strength.The cracking-and peak-moment formulas in the code for the design of concrete(GB 50010-2010)applied to the beams were both found to be acceptable.However,the calculation results of the maximum crack width following GB 50010-2010 and EN 1992-1-1:2004 were considerably conservative.In the context of GB 50010-2010,a revised formula for the crack width is proposed with modifications to two major factors:the average crack spacing and an amplification coefficient of the maximum crack width to the average spacing.The mean value of the ratio of the maximum crack width among the 12 test results and the relative calculation results from the revised formula is 1.017,which is better than the calculation result from GB 50010-2010.Therefore,the new formula calculates the crack width more accurately in high-strength concrete and high-strength steel reinforcement members.Finally,finite element models were established using ADINA software and validated based on the test results.This study provides an important reference for the development of high-strength concrete and highstrength steel reinforcement structures.

关键词： high-strength steel reinforcement high-strength concrete flexural behavior crack width

Ag-doped CNT/HAP nanohybrids in a PLLA bone scaffold show significant antibacterial activity

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Bio-Design and Manufacturing 2024年第2期7卷 105-120页

作者： Cijun Shuai Xiaoxin Shi Kai Wang yulong Gu feng Yang Pei feng State Key Laboratory of Precision Manufacturing for Extreme Service Performance College of Mechanical and Electrical EngineeringCentral South UniversityChangsha 410083China Institute of Additive Manufacturing Jiangxi University of Science and TechnologyNanchang 330013China College of Mechanical Engineering Xinjiang UniversityUrumqi 830017China

Bacterial infection is a major problem following bone implant surgery.Moreover,poly-l-lactic acid/carbon nanotube/hydroxyapatite(PLLA/CNT/HAP)bone scaffolds possess enhanced mechanical properties and show good bioactiv-ityregardingbonedefectregeneration.Inthisstudy,wesynthesizedsilver(Ag)-dopedCNT/HAP(CNT/Ag-HAP)nanohybrids via the partial replacing of calcium ions(Ca2+)in the HAP lattice with silver ions(Ag+)using an ion doping technique under hydrothermal conditions.Speciﬁcally,the doping process was induced using the special lattice structure of HAP and the abundant surface oxygenic functional groups of CNT,and involved the partial replacement of Ca2+in the HAP lattice by doped Ag+as well as the in situ synthesis of Ag-HAP nanoparticles on CNT in a hydrothermal environment.The result-ing CNT/Ag-HAP nanohybrids were then introduced into a PLLA matrix via laser-based powder bed fusion(PBF-LB)to fabricate PLLA/CNT/Ag-HAP scaffolds that showed sustained antibacterial activity.We then found that Ag+,which pos-sesses broad-spectrum antibacterial activity,endowed PLLA/CNT/Ag-HAP scaffolds with this activity,with an antibacterial effectiveness of 92.65%.This antibacterial effect is due to the powerful effect of Ag+against bacterial structure and genetic material,as well as the physical destruction of bacterial structures due to the sharp edge structure of CNT.In addition,the scaffold possessed enhanced mechanical properties,showing tensile and compressive strengths of 8.49 MPa and 19.72 MPa,respectively.Finally,the scaffold also exhibited good bioactivity and cytocompatibility,including the ability to form apatite layers and to promote the adhesion and proliferation of human osteoblast-like cells(MG63 cells).

关键词： Ag-doped Carbon nanotube/hydroxyapatite(CNT/HAP) Antibacterial properties Bone scaffold

La_(2)O_(3)-promoted Ni/H-ZSM-5 catalyzed aqueous-phase guaiacol hydrodeoxygenation to cyclohexanol

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Journal of Rare Earths 2023年第2期41卷 224-232页

作者： feng Lin Yudan Zhong yulong Ma Yonggang Sun Xiuqin Men Yingbo Zhu State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering College of Chemistry and Chemical EngineeringNingxia UniversityYinchuan 750021China

Hydrodeoxygenation(HDO)of renewable lignin-derived biomass in aqueous-phase to produce high value-added products is of great significance.However,developing new catalysts with high activity and excellent stability in an aqueous phase faces considerable challenges.Rare earth doping can effectively regulate the water exchange rate constant(WERC)value of the catalyst and play an important role in promoting the hydrolysis of ether bonds.Therefore,in this paper the bimetallic supported catalyst Ni-La_(2)O_(3)/H-ZSM-5 doped with rare earth metal La_(2)O_(3)was prepared,and used to catalyze the conversion of the lignin model co mpound guaiacol to cyclohexanol in the aqueous phase.The co nversion of guaiacol catalyzed by 10Ni-3La_(2)O_(3)/H-ZSM-5 reaches 100%,and the selectivity of the product cyclohexanol is 85%.A series of characterizations illustrate that the doping of La_(2)O_(3)causes the electron transfer between La_(2)O_(3)-Ni and changes the distribution of Ni,and a strong metal carrier interaction occurs between the bimetallic Ni-La_(2)O_(3)and H-ZSM-5.This can effectively promote the hydrolysis of the C-O ether bond in guaiacol and significantly improve the activity of the catalyst.The possible catalytic reaction mechanism of Ni-La_(2)O_(3)/H-ZSM-5 catalytic conversion of guaiacol was proposed.

关键词： La_(2)O_(3) Guaiacol Catalysis H-ZSM-5 Rare earths

Hydraulic Conductivity Characteristics of Hot Dry Rocks under Different Fracture Modes

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Acta Geologica Sinica(English Edition) 2021年第6期95卷 1915-1925页

作者： LIU Xin feng Bo LIU yulong YUAN Yilong Key Laboratory of Groundwater Resources and Environment Ministry of EducationJilin UniversityChangchun 130021China Jilin Provincial Key Laboratory of Water Resources and Environment Jilin UniversityChangchun 130021China

Enhanced geothermal system(EGS) is an effective method for developing and utilizing hot dry rock(HDR). The key to the effectiveness of EGS is the construction of an artificial fracture network. The permeability of fractures has severe effects on the heat transfer efficiency and sustainability of geothermal energy. However, the evolution characteristics of hydraulic conductivity under different failure modes have not been adequately studied for HDR. To clarify this, rocks with different failure modes were investigated by conducting thermal triaxial compression experiments, and the fluid seepage related to different rock failure modes was comprehensively investigated. The results showed that the characteristic stresses and crack surface roughness of the rock increased as the confining pressure increased. The permeability in the composited failure mode was the largest(11.4 μm;), followed by that in the Y-shaped shear failure mode(9.7 μm;), and that in the single-shear failure mode was the smallest(7.2 μm;). The confining pressures had an inhibitory effect on permeability. As the confining pressure increased from 5 to 30 MPa, the permeability decreased by 88.8%, 88.4%, and 89.9%, respectively. In contrast, the permeability was significantly enhanced by 128.3%, 94.6%, and 131% as the flow rate increased from 3 to 7 m L/min.

关键词： EGS hydraulic conductivity permeability experiment failure mode hot dry rock

Glutamine in suppression of lipopolysaccharide-induced piglet intestinal inflammation:The crosstalk between AMPK activation and mitochondrial function

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Animal Nutrition 2022年第3期10卷 137-147页

作者： Liuqin He Xihong Zhou Ziping Wu Yanzhong feng Di Liu Tiejun Li yulong Yin Hunan Provincial Key Laboratory of Animal Intestinal Function and Regulation Laboratory of Animal Nutrition and Human HealthCollege of Life SciencesHunan Normal UniversityChangsha410081China Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical AgricultureChinese Academy of SciencesHunan Provincial Key Laboratory of Animal Nutritional Physiology and Metabolic ProcessChangsha410125China Agricultural and Food Economics Queen's University BelfastNorthern IrelandBT95PXUnited Kingdom Heilongjiang Academy of Academy of Agricultural Sciences Harbin150086China

The study was conducted to investigate the regulatory mechanism of glutamine(Gln)on intestinal inflammation in an Escherichia coli lipopolysaccharide(E.coli LPS)-induced in vivo and in vitro models.Piglets(n=8)weaned at 21 d of age were fed a basal diet(control and LPS groups)or 1%Gln diet(Gln t LPS group)ad libitum for 4 weeks.On d 22,24,26 and 28,piglets in the LPS and Gln t LPS groups were intraperitoneally injected with E.coli LPS.Intestinal porcine epithelial cells(IPEC-J2)(n=6)induced by LPS were used to assess related mechanisms and compound C was used to inhibit adenosine 50-monophosphate-activated protein kinase(AMPK)activity.Our current results showed that compared with the LPS treatment,the Gln t LPS treatment had better growth performance and greater villus height(P<0.05),and the Gln t LPS treatment reduced the rate of diarrhea by 6.4%(P<0.05);the Gln t LPS treatment decreased serum tumor necrosis factor(TNF-ɑ),interleukin-6(IL-6),Kt,cortisol and insulin levels,whereas increased(P<0.05)serum immunoglobulin M and epidermal growth factor levels;the Gln t LPS treatment increased(P<0.05)the expression of aquaporins and AMPK pathwayassociated targets in the jejunum and ileum of piglets,whereas decreased the expression of ion transporters(P<0.05).The in vitro results showed that 4 mmol/L Gln administration could inhibit(P<0.05)cell apoptosis and interleukin-1b(IL-1b),IL-6 and TNF-ɑsecretion in LPS-induced IPEC-J2 cells,promote(P<0.05)mitochondrial respiratory metabolism and increase(P<0.05)the number of mitochondria and mitochondrial membrane potential.The activity of AMPK was elevated by 70%to 300%in Gln-treated IPEC-J2 cells under LPS challenge or normal conditions.Our results indicate that pre-administration of Gln to piglets suppresses intestinal inflammation by modulating the crosstalk between AMPK activation and mitochondrial function.

关键词： Glutamine Weaned piglet Intestinal inflammation AMPK Mitochondrial function

Multi-scale Incremental Analysis Update Scheme and Its Application to Typhoon Mangkhut(2018)Prediction

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Advances in Atmospheric Sciences 2023年第1期40卷 95-109页

作者： Yan GAO Jiali feng Xin XIA Jian SUN yulong MA Dongmei CHEN Qilin WAN Guangdong-Hong Kong-Macao Greater Bay Area Weather Research Center for Monitoring Warning and Forecasting Shenzhen 518038China CMA Earth System Modeling and Prediction Centre China Meteorological AdministrationBeijing 100081China

In the traditional incremental analysis update(IAU)process,all analysis increments are treated as constant forcing in a model’s prognostic equations over a certain time window.This approach effectively reduces high-frequency oscillations introduced by data assimilation.However,as different scales of increments have unique evolutionary speeds and life histories in a numerical model,the traditional IAU scheme cannot fully meet the requirements of short-term forecasting for the damping of high-frequency noise and may even cause systematic drifts.Therefore,a multi-scale IAU scheme is proposed in this paper.Analysis increments were divided into different scale parts using a spatial filtering technique.For each scale increment,the optimal relaxation time in the IAU scheme was determined by the skill of the forecasting results.Finally,different scales of analysis increments were added to the model integration during their optimal relaxation time.The multi-scale IAU scheme can effectively reduce the noise and further improve the balance between large-scale and small-scale increments in the model initialization stage.To evaluate its performance,several numerical experiments were conducted to simulate the path and intensity of Typhoon Mangkhut(2018)and showed that:(1)the multi-scale IAU scheme had an obvious effect on noise control at the initial stage of data assimilation;(2)the optimal relaxation time for large-scale and small-scale increments was estimated as 6 h and 3 h,respectively;(3)the forecast performance of the multi-scale IAU scheme in the prediction of Typhoon Mangkhut(2018)was better than that of the traditional IAU scheme.The results demonstrate the superiority of the multi-scale IAU scheme.

关键词： multi-scale incremental analysis updates optimal relaxation time 2-D discrete cosine transform GRAPES_Meso Typhoon Mangkhut(2018)

Rational design of unrestricted pRN1 derivatives and their application in the construction of a dual plasmid vector system for Saccharolobus islandicus

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mLife 2024年第1期3卷 119-128页

作者： Pengpeng Zhao Xiaonan Bi Xiaoning Wang Xu feng yulong Shen Guanhua Yuan Qunxin She CRISPR and Archaea Biology Research Center State Key Laboratory of Microbial Technology and Microbial Technology InstituteShandong UniversityQingdaoChina

Saccharolobus islandicus REY15A represents one of the very few archaeal models with versatile genetic tools,which include efficient genome editing,gene silencing,and robust protein expression systems.However,plasmid vectors constructed for this crenarchaeon thus far are based solely on the pRN2 cryptic plasmid.Although this plasmid coexists with pRN1 in its original host,early attempts to test pRN1-based vectors consistently failed to yield any stable host-vector system for Sa.islandicus.We hypothesized that this failure could be due to the occurrence of CRISPR immunity against pRN1 in this archaeon.We identified a putative target sequence in orf904 encoding a putative replicase on pRN1(target N1).Mutated targets(N1a,N1b,and N1c)were then designed and tested for their capability to escape the host CRISPR immunity by using a plasmid inter-ference assay.The results revealed that the original target triggered CRISPR immunity in this archaeon,whereas all three mutated targets did not,indicating that all the designed target mutations evaded host immunity.These mutated targets were then incorporated into orf904 individually,yielding corresponding mutated pRN1 backbones with which shuttle plasmids were constructed(pN1aSD,pN1bSD,and pN1cSD).Sa.islandicus transformation revealed that pN1aSD and pN1bSD were functional shuttle vectors,but pN1cSD lost the capability for replication.These results indicate that the missense mutations in the conserved helicase domain in pN1c inactivated the replicase.We further showed that pRN1-based and pRN2-based vectors were stably maintained in the archaeal cells either alone or in combination,and this yielded a dual plasmid system for genetic study with this important archaeal model.

关键词： archaeal genetics CRISPR-Cas CRISPR escape mutations dual plasmid vectors Saccharolobus-E.coli shuttle vectors

Self-assembled Cyclodextrin Metal-Organic Frameworks on Graphene Oxide as Filter Membrane for Tracelevel Naringin Pre-enrichment before Analysis

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Journal of Wuhan University of Technology(Materials Science) 2022年第3期37卷 336-341页

作者：李媛媛 CHEN Na ZHU Nan feng Xiangzhi MA yulong JI Wenxin SUN Yonggang State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering Ningxia UniversityYinchuan 750021China College of Chemistry and Chemical Engineering Ningxia UniversityYinchuan 750021China

A green,renewable composite was designed and fabricated based on self-assembly of cyclodextrin metal-organic framework(CD-MOF)on graphene oxide(GO).Then,the GO@CD-MOF was embedded in 0.45μm PTFE membrane to produce a dual-functional membrane which could carry out sample enrichment by capturing naringin molecules.The membrane filter was further improved by investigating the effects of the experimental parameters including amount of GO@CD-MOF,enrichment time and elution solvent on enrichment efficiency of naringin.Further,the present method had been successfully applied to citrus sample and obtained satisfied recovery value(79.7%-100.3%).Moreover,the extraction of naringin can be achieved for 2 min,and GO@CD-MOF loaded membrane can be reused at least for 5 times.The results demonstrate that the fabrication of the novel filter membrane based on GO@CD-MOF is a fast,simple and reliable,and possesses great potential in the determination of naringin from real samples by dual-function of separation and enrichment.

关键词： cyclodextrin metal-organic framework graphene oxide membrane filter naringin enrichment