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An atmosphere-breathing propulsion system using inductively coupled plasma source

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Chinese Journal of Aeronautics 2023年第5期36卷 223-238页

作者： Peng ZHENG Jianjun WU Yu ZHANG Bixuan CHE yuanzheng zhao College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

CubeSats have attracted more research interest recently due to their lower cost and shorter production time.A promising technology for CubeSat application is atmosphere-breathing electric propulsion,which can capture the atmospheric particles as propulsion propellant to maintain longterm mission at very low Earth *** paper designs an atmosphere-breathing electric propulsion system for a 3 U CubeSat,which consists of an intake device and an electric thruster based on the inductively coupled *** capture performance of intake device is optimized considering both particles capture efficiency and compression *** plasma source is also analyzed by experiment and ***,the thrust performance is also estimated when taking into account the intake *** results show that it is feasible to use atmosphere-breathing electric propulsion technology for CubeSats to compensate for aerodynamic drag at lower Earth orbit.

关键词： Atmosphere-Breathing Electric Propulsion(ABEP) CubeSat Inductively coupled plasma Intake device Very Low Earth Orbit(VLEO)

内生枯草芽胞杆菌WZ10对马铃薯枯萎病防效及功能测定

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中国生物防治学报 2024年第2期40卷 370-377页

作者：赵远征张超张岩徐利敏周洪友王东内蒙古自治区农牧业科学院呼和浩特010031 内蒙古农业大学呼和浩特010018 生物农药创制与资源利用重点实验室呼和浩特010018

为明确枯草芽胞杆菌WZ10的生物学功能及对马铃薯枯萎病的室内防治效果。本研究利用Salkowski’s比色法和分光光度法、室内盆栽试验对菌株WZ10促生能力进行测定;通过室内防病试验和生理生化测定分析菌株WZ10的防病效果;并利用透明圈法对... 详细信息

为明确枯草芽胞杆菌WZ10的生物学功能及对马铃薯枯萎病的室内防治效果。本研究利用Salkowski’s比色法和分光光度法、室内盆栽试验对菌株WZ10促生能力进行测定;通过室内防病试验和生理生化测定分析菌株WZ10的防病效果;并利用透明圈法对其解磷、解钾能力进行测定。结果表明,枯草芽胞杆菌WZ10具有产IAA和解无机磷能力,并对马铃薯植株的生长有明显的促生作用,与对照植株相比,接种菌株WZ10后马铃薯植株的株高、根长和鲜重均显著增加,分别提高了14.34%、19.75%和77.07%,马铃薯植株的PPO、POD、SOD酶活性和可溶性蛋白含量显著升高。同时,菌株WZ10对马铃薯枯萎病的室内防治效果达80.65%,显著高于30%甲霜·噁霉灵水剂处理。菌株WZ10具有较强的促生能力,且对马铃薯枯萎病具有显著的防治效果,该研究可为后续菌株WZ10功能开发和枯萎病病害防治奠定基础。

关键词：枯草芽胞杆菌马铃薯枯萎病促生防治效果

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棘孢木霉PT-29与枯草芽孢杆菌S-16共培养对马铃薯枯萎病的防控作用

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河南农业科学 2024年第3期53卷 95-102页

作者：张尹强郝建秀赵远征王东周洪友内蒙古农业大学园艺与植物保护学院内蒙古呼和浩特010018 生物农药创制与资源利用自治区高等学校重点实验室内蒙古呼和浩特010018 内蒙古自治区农牧业科学院植物保护研究所内蒙古呼和浩特010031

马铃薯枯萎病是一种土传真菌病害,可对马铃薯整个生育期造成严重危害,在全国主要马铃薯产区都有不同程度的发生。为减少化学药剂防治马铃薯枯萎病带来的弊端,提高生防菌剂效果,研究了棘孢木霉(Trichoderma asperellum)PT-29与枯草芽孢杆... 详细信息

马铃薯枯萎病是一种土传真菌病害,可对马铃薯整个生育期造成严重危害,在全国主要马铃薯产区都有不同程度的发生。为减少化学药剂防治马铃薯枯萎病带来的弊端,提高生防菌剂效果,研究了棘孢木霉(Trichoderma asperellum)PT-29与枯草芽孢杆菌(Bacillus subtilis)S-16对马铃薯枯萎病主要致病菌尖孢镰刀菌(Fusarium oxysporum)的抑菌效果,并通过盆栽试验测定了2株菌共培养发酵液对马铃薯枯萎病的防治效果及对马铃薯相关防御酶活性的影响。结果表明,2株菌单培养和3种比例共培养发酵液对尖孢镰刀菌均有抑制效果且以PT-29与S-16共培养发酵液组合B1T1(比例为1∶1)抑制效果最佳;单培养S-16的发酵液(B)处理对马铃薯枯萎病的防效为60.09%,单培养PT-29的发酵液(T)处理对马铃薯枯萎病的防效为54.85%,B1T1处理对马铃薯枯萎病的防效达到73.44%。此外,B1T1+FO(接种尖孢镰刀菌)处理的马铃薯叶片过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、过氧化物酶(POD)、苯丙氨酸解氨酶(PAL)活性明显高于FO处理,峰值相比于FO处理分别提高56.44%、766.89%、111.84%、179.34%。综上所述,PT-29与S-16共培养发酵液对马铃薯枯萎病的防治效果高于单培养发酵液,为复合微生物防治马铃薯枯萎病提供了理论支持。

关键词：马铃薯枯萎病棘孢木霉枯草芽孢杆菌防治效果防御酶

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基于MaxEnt模型的腐烂茎线虫在内蒙古地区适生区预测

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生物安全学报（中英文） 2024年第2期33卷 161-168页

作者：杨帆赵远征张晓明王东周洪友内蒙古农业大学园艺与植物保护学院内蒙古呼和浩特010018 内蒙古自治区农牧业科学院植物保护研究所内蒙古呼和浩特010031 内蒙古农业大学草原与资源环境学院内蒙古呼和浩特010018

【目的】为保障马铃薯产业健康发展,加强腐烂茎线虫的检疫防控工作,对其在内蒙古地区的适生区进行预测分析。【方法】根据腐烂茎线虫在我国最新的分布和环境数据,通过MaxEnt生态位模型和ArcGIS软件,预测当前和未来气候条件下腐烂茎线虫... 详细信息

【目的】为保障马铃薯产业健康发展,加强腐烂茎线虫的检疫防控工作,对其在内蒙古地区的适生区进行预测分析。【方法】根据腐烂茎线虫在我国最新的分布和环境数据,通过MaxEnt生态位模型和ArcGIS软件,预测当前和未来气候条件下腐烂茎线虫在内蒙古地区的适生区。【结果】MaxEnt模型的AUC平均值为0.929,预测结果准确可靠。预测结果显示:当前气候条件下腐烂茎线虫在内蒙古地区的适生区面积为41.8万km^(2),占全区面积的35.31%。研究表明,在2021—2040年和2041—2060年,腐烂茎线虫在内蒙古地区的总适生区面积将不断扩大;其中在SSP1_2.6气候情景下,在赤峰市、通辽市和兴安盟将出现腐烂茎线虫的高适生区;在SSP3_7.0气候情景下,在鄂尔多斯市、赤峰市、通辽市将出现腐烂茎线虫高适生区。利用Jackknife刀切法计算得到影响腐烂茎线虫分布的主导环境因子为温度季节性变化方差、最湿月降雨量、最冷季平均温、昼夜温差月均温、最湿季平均温。【结论】腐烂茎线虫在内蒙古地区有进一步扩散的风险,建议在未来气候情景下出现腐烂茎线虫高度适生区的盟市,应加强调运检疫和疫情监测,防止腐烂茎线虫进一步扩散。

关键词：腐烂茎线虫 MaxEnt 潜在适生区气候模式

Characteristics of plasma in a novel laser-assisted pulsed plasma thruster

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Plasma Science and Technology 2022年第7期24卷 3-14页

作者： yuanzheng zhao Yu ZHANG Jianjun WU Yang OU Peng ZHENG College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073People's Republic of China

A novel laser-assisted pulsed plasma thruster(LA-PPT)is proposed as an electric propulsion thruster,which separates laser ablation and electromagnetic *** aims for a higher specific impulse than that achieved with conventional *** to the short-time discharge and the novel configuration,the physical mechanism of the discharge is *** and spatial-resolved optical emission spectroscopy was applied to investigate the variation in the plasma properties in the thruster discharge *** plasma species,electron temperature,and electron density were obtained and *** investigation revealed that there were H_(α),H_(β),H_(γ),H_(ε) atoms,CⅠ,CⅡ,CⅢ,CⅣ,ClⅠ,ClⅡparticles,and a small amount of CH,C_(3),C_(2),H_(2) neutral molecular groups in the *** electron temperature of the discharge channel of the thruster was within 0.6–4.9 e V,and the electron density was within(1.1–3.0)×10^(18)cm^(-3),which shows that the optical emission spectroscopy method is to measure the electron excitation temperature and electron density in heavy *** the Langmuir probe method is to measure the temperature and density of free *** use of laser instead of spark plug as the ignition mode significantly changed the plasma distribution in the discharge *** the conventional PPT,which has high electron density near the thruster surface,LAPPT showed relatively large electron density at the thruster outlet,which increased the thruster specific *** addition,the change in the ignition mode enabled the electron density in the LA-PPT discharge channel to be higher than that in the conventional *** proves that the ignition mode with laser replacing the spark plug effectively optimised the PPT performance.

关键词： laser-assisted pulsed plasma thruster plasma properties time and spatial-resolved optical emission spectroscopy

The ablation characteristics of laser-assisted pulsed plasma thruster with metal propellant

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Plasma Science and Technology 2021年第10期23卷 60-71页

作者： yuanzheng zhao Sheng Tan Jianjun Wu Yu Zhang Yang Ou Peng Zheng College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073People's Republic of China

In this study,a laser-assisted pulsed plasma thruster(LA-PPT)with a novel configuration is proposed as an electric propulsion thruster which separates laser ablation and electromagnetic *** to the unique structure of the thruster,metals can also be used as propellants,and a higher specific impulse is *** ablation quality,morphology,and plume distribution of various metals(aluminium alloy,red copper,and carbon steel)with different laser energies were studied *** ablation morphology and plume distribution of red copper were more uniform,as compared to those of other metals,and the ablation quality was higher,indicating its greater suitability for *** plume generated by nanosecond laser ablation of aluminium alloy expanded faster,which indicated that the response time of the thruster with aluminium alloy as the propellant was *** addition,when the background pressure was 0.005 Pa,an obvious plume splitting phenomenon was observed in the ablation plume of the pulsed laser irradiating aluminium alloy,which may significantly reduce the utilisation rate of the propellant.

关键词： plasma plume expansion dynamics plume splitting phenomenon nanosecond laser ablation laser-assisted pulsed plasma thruster

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不同农业措施对青贮玉米品质影响

草原与草业 2024年第1期36卷 25-29页

作者：张斌赵远征王怡博郑娜张宇李松树候伟峰武川县农牧技术推广中心呼和浩特011700 内蒙古自治区农牧业科学院呼和浩特010031 内蒙古农业大学呼和浩特010018 兴安盟农牧科学研究所乌兰浩特137400

为明确我国青贮玉米品质发展现状及影响其品质的关键因素,针对提高青贮玉米品质的问题,从玉米品种选择、栽培管理技术、有害生物防治三方面进行阐述,明确了通过选择适合的青贮玉米品种,合理的栽培技术及科学的有害生物防治措施,能够显... 详细信息

为明确我国青贮玉米品质发展现状及影响其品质的关键因素,针对提高青贮玉米品质的问题,从玉米品种选择、栽培管理技术、有害生物防治三方面进行阐述,明确了通过选择适合的青贮玉米品种,合理的栽培技术及科学的有害生物防治措施,能够显著提高青贮玉米的品质,为今后青贮玉米的相关研究及产业发展提供了理论参考。

关键词：青贮玉米饲料品质栽培措施有害生物防治

Two types of coumarins-specific enzymes complete the last missing steps in pyran- and furanocoumarins biosynthesis

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Acta Pharmaceutica Sinica B 2024年第2期14卷 869-880页

作者： Yucheng zhao Yuedong He Liangliang Han Libo Zhang yuanzheng Xia Fucheng Yin Xiaobing Wang Deqing zhao Sheng Xu Fei Qiao Yibei Xiao Lingyi Kong Department of Resources Science of Traditional Chinese Medicines School of Traditional Chinese Pharmacyand State Key Laboratory of Natural MedicinesChina Pharmaceutical UniversityNanjing 210009China College of Bioscience and Biotechnology Hunan Agricultural UniversityChangsha 410128China Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines Department of Natural Medicinal ChemistryChina Pharmaceutical UniversityNanjing 210009China Key Laboratory of Crop Gene Resources and Germplasm Enhancement in Southern China Ministry of AgricultureTropical Crops Genetic Resources InstituteChinese Academy of Tropical Agricultural SciencesHaikou 517317China Institute of Botany Jiangsu Province and Chinese Academy of SciencesNanjing 210014China Department of Pharmacology School of Pharmacyand State Key Laboratory of Natural MedicinesChina Pharmaceutical UniversityNanjing 210009China

Pyran-and furanocoumarins are key representatives of tetrahydropyrans and tetrahydrofurans,respectively,exhibiting diverse physiological and medical ***,the biosynthetic mechanisms for their core structures remain poorly *** we combined multiomics analyses of biosynthetic enzymes in Peucedanum praeruptorum and in vitro functional verification and identified two types of key enzymes critical for pyran and furan ring biosynthesis in *** included three distinct *** prenyltransferases(PpPT1e3)responsible for the prenylation of the simple coumarin skeleton 7 into linear or angular precursors,and two novel CYP450 cyclases(PpDC and PpOC)crucial for the cyclization of the linear/angular precursors into either tetrahydropyran or tetrahydrofuran *** analyses of cyclases indicated that acid/base-assisted epoxide ring opening contributed to the enzyme-catalyzed tetrahydropyran and tetrahydrofuran ring *** possible acid/base-assisted catalytic mechanisms of the identified cyclases were theoretically investigated and assessed using site-specific *** identified two possible acidic amino acids Glu303 in PpDC and Asp301 in PpOC as vital in the catalytic *** study provides new enzymatic tools in the epoxide formation/epoxide-opening mediated cascade reaction and exemplifies how plants become chemically diverse in terms of enzyme function and catalytic process.

关键词： Tetrahydropyrans Tetrahydrofurans Baldwin rules Coumarins CYP450cyclase

颈动脉周围脂肪衰减指数与缺血性脑卒中的关系

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中国实用神经疾病杂志 2024年第4期27卷 420-424页

作者：赵芳赵源征周晨光王建平郑州大学第五附属医院河南郑州450052

目的评估颈动脉周围脂肪炎症与缺血性脑卒中的关系。方法筛选2021-01—2022-09郑州大学第五附属医院的248例受试者,按近6个月内有无发生过颈动脉供血区域脑梗死或TIA分为有症状组(n=89)和无症状组(n=159)。症状组选择症状侧颈动脉狭... 详细信息

目的评估颈动脉周围脂肪炎症与缺血性脑卒中的关系。方法筛选2021-01—2022-09郑州大学第五附属医院的248例受试者,按近6个月内有无发生过颈动脉供血区域脑梗死或TIA分为有症状组(n=89)和无症状组(n=159)。症状组选择症状侧颈动脉狭窄最严重的斑块,无症状组选择颈动脉狭窄最严重的斑块,通过CT血管造影(CTA)评估斑块段内周围脂肪衰减指数(FAI)与无症状组最狭窄一侧的颈动脉周围FAI。应用Logistic回归分析和受试者工作特征(ROC)分析FAI与缺血性脑卒中的关系。结果有症状组的FAI值高于无症状组[(-49.0±10.7)Hu比(-64.1±18.7)Hu,P<0.001]。二元Logistic回归分析显示,调整混杂因素后颈动脉FAI与缺血性脑卒中密切相关(OR=1.078,95%CI:1.053~1.103,P<0.01),ROC曲线显示曲线下面积(AUC)为0.761。结论症状组颈动脉周围FAI增加,颈部斑块相关的炎症反应已延伸至血管周围脂肪组织(PVAT),颈动脉周围脂肪组织的炎症反应可通过颈部CTA识别。

关键词：缺血性脑卒中颈动脉脂肪衰减指数 CT血管造影炎症反应