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A statistical analysis of the Kappa-type energy spectrum distribution of radiation belt electrons observed by Van Allen Probes

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Earth and Planetary Physics 2024年第2期8卷 368-374页

作者： LuHuai jiao Xin Ma YuanNong Zhang TaiFeng Jin Song Fu BinBin ni Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China

The energy spectrum of energetic electrons is a key factor representing the dynamic variations of Earth’s Van Allen radiation *** measurements have indicated that the commonly used Maxwellian and Kappa distributions are inadequate for capturing the realistic spectral distributions of radiation belt *** we adopt the Kappa-type(KT)distribution as the fitting function and perform a statistical analysis to investigate the radiation belt electron flux spectra observed by the Van Allen *** calculating the optimal values of the key KT distribution parameters(i.e.,κandθ2)from the observed spectral shapes,we fit the radiation belt electron fluxes at different L-shells under different geomagnetic *** this manner,we obtain typical values of the KT distribution parameters,which are statistically feasible for modeling the radiation belt electron flux profiles during either geomagnetically quiet or active periods.A comparison of the KT distribution model results with those using the Maxwellian or Kappa distribution reveals the advantage of the KT distribution for studying the overall properties of the radiation belt electron spectral distribution,which has important implications for deepening the current understanding of the radiation belt electron dynamics under evolving geomagnetic conditions.

关键词： radiation belt electron Kappa-type distribution fitting geomagnetic storm

Study on the green extraction of corncob xylan by deep eutectic solvent

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Grain & Oil Science and Technology 2024年第1期7卷 50-59页

作者： Bingyu jiao Le Wang Haitao Gui Zifu ni Rong Du Yuansen Hu School of Biological Engineering National Engineering Research Center of Wheat and Corn Further ProcessingZhengzhou 450001China

Corn as one of the world's major food crops,its by-product corn cob is also rich in ***,the unreasonable utilization of corn cob often causes the environmental pollution,waste of resources and other *** one of the most abundant polymers in nature,xylan is widely used in food,medicine,materials and other *** cob is rich in xylan,which is an ideal raw material for extracting ***,the intractable lignin is covalently linked to xylan,which increases the difficulty of xylan *** has been reported that the deep eutectic solvent(DES)could preferentially dissolve lignin in biomass,thereby dissolving the ***,the xylan in the extract was separated by ethanol precipitation *** xylan precipitate was obtained after centrifugation,while the supernatant was *** components of the supernatant after ethanol precipitation were separated by the rotary *** ethanol,water and DES were collected for the subsequent extraction of corn cob *** this study,a novel way was provided for the green production of corn cob *** DES was used to extract xylan from corn cob which was used as the raw *** effects of solid-liquid ratio,reaction time,reaction temperature and water content of DES on the extraction rate of corn cob xylan were investigated by the single factor ***,the orthogonal test was designed to optimize the xylan extraction *** structure of corn cob xylan was analyzed and *** results showed that the optimum extraction conditions of corn cob xylan were as follows:the ratio of corn cob to DES was 1:15(g:mL),the extraction time was 3 h,the extraction temperature was 60℃,and the water content of DES was 70%.Under these conditions,the extraction rate of xylan was 16.46%.The extracted corn cob xylan was distinctive triple helix of polysaccharide,which was similar to the structure of commercially available *** was effectively and workably extracted from corn

关键词： Corncob Deep eutectic solvent Xylan Process optimization Extraction

Evidence for the paternal mitochondrial DNA in the crucian carp-like fish lineage with hybrid origin

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Science China(Life Sciences) 2020年第1期63卷 102-115页

作者： Shi Wang ni jiao Lu Zhao Meiwen Zhang Pei Zhou Xuexue Huang Fangzhou Hu Conghui Yang Yuqin Shu Wuhui Li Chun Zhang Min Tao Bo Chen Ming Ma Shaojun Liu State Key Laboratory of Developmental Biology of Freshwater Fish Hunan Normal UniversityChangsha 410081China College of Life Sciences Hunan Normal UniversityChangsha 410081China College of Chemistry and Chemical Engineering Hunan Normal UniversityChangsha 410081China Key Laboratory of Tropical and Subtropical Fisheries Resource Application and Cultivation Ministry of AgriculturePearl River Fisheries Research InstituteChinese Academy of Fishery SciencesGuangzhou 510380China

In terms of taxonomic status,common carp(Cyprinus carpio,Cyprininae)and crucian carp(Carassius auratus,Cyprininae)are different species;however,in this study,a newborn homodiploid crucian carp-like fish(2n=100)(2nNCRC)lineage(F1–F3)was established from the interspecific hybridization of female common carp(2n=100)×male blunt snout bream(Megalobrama amblycephala,Cultrinae,2n=48).The phenotypes and genotypes of 2 n NCRC differed from those of its parents but were closely related to those of the existing diploid crucian *** further sequenced the whole mitochondrial(mt)genomes of the 2n NCRC lineage from F1 to *** paternal mt DNA fragments were stably embedded in the mt-genomes of F1–F3 generations of 2n NCRC to form chimeric DNA *** with this chimeric process,numerous base sites of F1–F3 generations of 2 n NCRC underwent *** of these mutation sites were consistent with the existing diploid crucian ***,the mt DNA organization and nucleotide composition of 2n NCRC were more similar to those of the existing diploid crucian carp than those of the *** inheritable chimeric DNA fragments and mutant loci in the mt-genomes of different generations of 2nNCRC provided important evidence of the mt DNA change process in the newborn lineage derived from hybridization of different *** findings demonstrated for the first time that the paternal mt DNA were transmitted into the mt-genomes of homodiploid lineage,which provided new insights into the existence of paternal mt DNA in the mt DNA inheritance.

关键词： hybridization homodiploid common carp blunt snout bream crucian carp mitochondrial genome genetic evolution

Effects of dietary Clostridium butyricum and rumen protected fat on meat quality,oxidative stability,and chemical composition of finishing goats

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Journal of Animal Science and Biotechnology 2024年第2期15卷 911-924页

作者： Meimei Zhang Zhiyue Zhang Xinlong Zhang Changming Lu Wenzhu Yang Xiaolai Xie Hangshu Xin Xiaotan Lu Mingbo ni Xinyue Yang Xiaoyang Lv Peixin jiao College of Animal Science and Technology Northeast Agricultural UniversityHarbin 150030People’s Republic of China Lethbridge Research and Development Centre Lethbridge T1J 4B1Canada School of Agriculture and Food Sciences The University of QueenslandGattonQLD 4343Australia International Joint Research Laboratory in Universities of Jiangsu Province of China for Domestic Animal Germplasm Resources and Genetic Improvement Yangzhou 225009China

Background Clostridium butyricum(CB)is a probiotic that can regulate intestinal microbial composition and improve meat *** protected fat(RPF)has been shown to increase the dietary energy density and provide essential fatty ***,it is still unknown whether dietary supplementation with CB and RPF exerts beneficial effects on growth performance and nutritional value of goat *** study aimed to investigate the effects of dietary CB and RPF supplementation on growth performance,meat quality,oxidative stability,and meat nutritional value of finishing ***-two goats(initial body weight,20.5±0.82 kg)were used in a completely randomized block design with a 2 RPF supplementation(0 vs.30 g/d)×2 CB supplementation(0 vs.1.0 g/d)factorial treatment *** experiment included a 14-d adaptation and 70-d data and sample collection *** goats were fed a diet consisted of 400 g/kg peanut seedling and 600 g/kg corn-based concentrate(dry matter basis).Result Interaction between CB and RPF was rarely observed on the variables measured,except that shear force was reduced(P<0.05)by adding CB or RPF alone or their combination;the increased intramuscular fat(IMF)content with adding RPF was more pronounced(P<0.05)with CB than without CB *** pH24h(P=0.009),a*values(P=0.007),total antioxidant capacity(P=0.050),glutathione peroxidase activities(P=0.006),concentrations of 18:3(P<0.001),20:5(P=0.003)and total polyunsaturated fatty acids(P=0.048)were increased,whereas the L*values(P<0.001),shear force(P=0.050)and malondialdehyde content(P=0.044)were decreased by adding ***,CB supplementation increased essential amino acid(P=0.027),flavor amino acid(P=0.010)and total amino acid contents(P=0.024)as well as upregulated the expression of lipoprotein lipase(P=0.034)and peroxisome proliferator-activated receptorγ(PPARγ)(P=0.012),and downregulated the expression of stearoyl-CoA desaturase(SCD)(P=0.034).The RPF supplementation increased dry

关键词： Chemical composition Clostridium butyricum Goats Meat quality Oxidative stability Rumen protected fat

Bulging Distortion of Austenitic Stainless Steel Sheet on the Partially Penetrated Side of Non-Penetration Lap Laser Welding Joint

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 286-295页

作者： Chengwu Yao Enze Liu Jiaming ni Binying nie Shanghai Key Laboratory of Materials Laser Processing and Modification School of Material Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Aerospace Precision Machinery Institute Shanghai 201600China Chemical and Biological Engineering College Yichun UniversityYichun 336000China

Non-penetration laser welding of lap joints in austenitic stainless steel sheets is commonly preferred in fields where the surface quality is of utmost ***,the application of non-penetration welded austenitic stainless steel parts is limited owing to the micro bulging distortion that occurs on the back surface of the partial penetration *** this paper,non-penetration lap laser welding experiments,were conducted on galvanized and SUS304 austenitic stainless steel plates using a fiber laser,to investigate the mechanism of bulging distortion.A comparative experiment of DC01 galvanized steel-Q235 carbon steel lap laser welding was carried out,and the deflection and distortion profile of partially penetrated side of the sheets were measured using a noncontact laser *** addition,the cold-rolled SUS304 was subjected to heat holding at different temperatures and water quenching after bending to characterize its microstructure under tensile and compressive *** results show that,during the heating stage of the thermal cycle of laser lap welding,the partial penetration side of the SUS304 steel sheet generates compressive stress,which extrudes the material in the heat-affected zone to the outside of the back of the SUS304 steel sheet,thereby forming a *** findings of these experiments can be of great value for controlling the distortion of the partial penetrated side of austenitic stainless steel sheet during laser non-penetration lap welding.

关键词： Non-penetration lap laser welding Bulging distortion Austenitic stainless steel Compressive stress Tension stress

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痴呆患者日常生活能力下降模式的研究

中华老年医学杂志 2012年第5期31卷 363-366页

作者：金煜倪姣娜吴炯浙江医院神经内科杭州310013

目的了解痴呆患者日常生活能力（ADL）下降的情况和模式。方法收集痴呆患者204例，其中阿尔茨海默病（AD）106例，血管性痴呆（VD）54例，其他类型痴呆44例；根据简易智能状态检查表（MMSE），轻、中、重度痴呆患者分别为42例、37例、12... 详细信息

目的了解痴呆患者日常生活能力（ADL）下降的情况和模式。方法收集痴呆患者204例，其中阿尔茨海默病（AD）106例，血管性痴呆（VD）54例，其他类型痴呆44例；根据简易智能状态检查表（MMSE），轻、中、重度痴呆患者分别为42例、37例、125例。采用Barthel指数（BI）对患者ADL进行测评，比较不同认知程度、AD和VD痴呆及不同文化程度痴呆患者的日常生活能力。结果痴呆患者ADL保留最多项目的是大便（48．5％）、小便（44．1％）和梳洗（40．2％）三项，能力保留最少的项目是上楼梯（25．5％）和洗澡（18．1%）；随着认知损害的加重，痴呆患者的BI得分也是明显下降，其中重度（23．2士29．3）分、中度（65．5±26．4）分、轻度痴呆（87．4土22．7）分，其差异有统计学意义（X^2=99．686，P=0．000）；AD与VD比较，日常活动能力保留率（16．98％～53．77％）明显高于VD患者（1．85％～33．33％）；不同文化程度痴呆患者BI得分小学及以下（40．1±39．0）分、中学组（45．3±39．6）分、大专及以上组（53．1±37．7）分，其差异无统计学意义（X^2=3．653，P-0．161）。结论中国痴呆患者最易丧失的日常生活功能是洗澡、上楼梯，最易保留的是大便、小便和梳洗。日常生活能力受痴呆程度和类型影响，但与文化程度无明显相关性。

关键词：痴呆日常生活活动

不连续路面标线对跟车间距调节行为的影响机理

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中国公路学报 2021年第5期34卷 182-193页

作者：丁乃侃朱顺应刘兵焦泥沙武汉理工大学交通学院湖北武汉430063 武汉工程大学土木工程与建筑学院湖北武汉430074 湖北省交通运输厅规划研究室湖北武汉430030

为了解析不连续路面标线对跟车间距调节行为的影响机理,深入挖掘了不连续路面标线的视觉信息特征,提出单色路面标线(2,3,4 m黄色标线铺设周期长度,即Y-2 m, Y-3 m, Y-4 m)和双色路面标线[1根黄色标线连接1根红色标线(1Y+1R)、2根黄色标... 详细信息

为了解析不连续路面标线对跟车间距调节行为的影响机理,深入挖掘了不连续路面标线的视觉信息特征,提出单色路面标线(2,3,4 m黄色标线铺设周期长度,即Y-2 m, Y-3 m, Y-4 m)和双色路面标线[1根黄色标线连接1根红色标线(1Y+1R)、2根黄色标线连接2根红色标线(2Y+2R)、3根黄色标线连接3根红色标线(3Y+3R)]2种不连续路面标线的设计形式,并将该设计具体呈现于实际的高速公路路面上。通过摄像法间接采集了车辆连续通过6个观测断面的跟车行驶车头时距、车头间距和行车速度特征数据。此6个观测断面依车流行进方向两两之间间隔100 m均匀设置,构成500 m的试验区域,其中观测断面1和6分别代表起始和终止断面,观测断面2~5之间为路面标线铺设区域。研究结果表明:从总体来看,铺设不连续路面标线后,试验路段跟车车距(车头时距、车头间距)相较于铺设前有显著的增大,而行车速度有显著的减小,其中1Y+1R方案下的车距增大和速度减小幅度均最大,分别为0.61 s, 3.6 m和5.1 km·h^(-1);从观测断面来看,铺设不连续路面标线后,跟车车距和行车速度随着车辆在试验区域内行进,分别呈现出一致的增大和减小的趋势,且通过对比观测断面1和5发现,1Y+1R方案下跟车车距和行车速度的断面变化幅度最大,分别为0.62 s, 5.7 m和5.3 km·h^(-1);相同铺设周期条件下,双色路面标线可以产生更为显著的跟车车距调节效果。基于以上研究结果,从驾驶人距离感知、速度感知和颜色变化3个层面,深入剖析了"不连续效应"和边缘率对跟车间距调节行为的影响机理,并讨论了距离感知和速度感知对跟车行为的协同作用过程。研究结果可为视觉干预措施的进一步完善、优化提供理论支撑,并为探索低成本的交通事故预防措施提供新的应用实例。

关键词：交通工程不连续路面标线路上试验车间距调节行为跟车视觉感知

Tuning oxygen redox via transition-metal cation species

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Science China Chemistry 2024年第7期67卷 2130-2131页

作者： Sichen jiao Xuelong Wang Xiqian Yu Beijing Frontier Research Center on Clean Energy Institute of PhysicsChinese Academy of SciencesBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Lithium-rich layered oxides with a general formula of Li[Li_(x)ni_(y)MnzCo_(1–x–y–z)]O_(2)(Li-rich NMCs,elements in bracket reside in the same layer)are recognized as promising candidates for the next generation hi... 详细信息

关键词： lithium oxides transition

五味子咀嚼片的HPLC-DAD指纹图谱研究

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中草药 2015年第16期46卷 2413-2416页

作者：于敏王雪焦安妮尹春梅焦连庆吉林省中医药科学院植物化学所吉林长春130012 吉林农业大学中药材学院吉林长春130118 沈阳师范大学辽宁沈阳110034

目的建立五味子咀嚼片的HPLC-DAD指纹图谱,对10个不同批次的五味子咀嚼片进行质量评价。方法使用Luna C18色谱柱（250 mm×4.6 mm,5μm）,乙腈-0.05%磷酸水溶液为流动相进行梯度洗脱,体积流量1.0 m L/min,柱温35℃,检测波长220 nm,进样... 详细信息

目的建立五味子咀嚼片的HPLC-DAD指纹图谱,对10个不同批次的五味子咀嚼片进行质量评价。方法使用Luna C18色谱柱（250 mm×4.6 mm,5μm）,乙腈-0.05%磷酸水溶液为流动相进行梯度洗脱,体积流量1.0 m L/min,柱温35℃,检测波长220 nm,进样量20μL。结果通过测定10批五味子咀嚼片的HPLC-DAD图谱,建立了指纹图谱的共有模式,HPLC-DAD指纹图谱共有峰39个,相似度为0.914-0.999;确认了五味子醇甲、五味子醇乙、五味子酯甲、五味子乙素、五味子丙素、丹参素钠、丹酚酸B、隐丹参酮、丹参酮IIA、原儿茶醛、木犀草苷、蒙花苷。结论方法准确、可靠、重现性好,为评价五味子咀嚼片的质量提供了科学依据。

关键词：五味子咀嚼片指纹图谱高效液相色谱法-二极管阵列检测器五味子醇甲五味子醇乙五味子酯甲五味子乙素五味子丙素丹参素钠丹酚酸B 隐丹参酮丹参酮IIA 原儿茶醛木犀草苷蒙花苷