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Discriminating the deterioration of walnut kernels stored at different relative humidities by GC-MS coupled with chemometrics
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作者 PAN Lihua WANG Weijia +3 位作者 LEI Yanghao LUO Shuizhong ZHENG Zhi ZHONG Xiyang 《农业工程学报》 北大核心 2025年第23期293-302,共10页
To explore the effects of relative humidity(RH)on the quality of walnut kernels and establish a rapid,effective method/model for identifying their deterioration degree,walnut kernels were stored at 45℃for 90 days und... To explore the effects of relative humidity(RH)on the quality of walnut kernels and establish a rapid,effective method/model for identifying their deterioration degree,walnut kernels were stored at 45℃for 90 days under different RH conditions(35%,50%,65%and 80%)in this study.Every 15 days,changes in the kernels'color,acid values(AV),peroxide values(POV),fatty acid composition,contents of total phenols and soluble quinones,synchronous fluorescence spectra,and the compositions/contents of volatile organic compounds(VOCs)were analyzed.Partial least squares discriminant analysis(PLS-DA)and variable importance in projection(VIP)were used to conduct differential analysis of VOCs.The deterioration degree of walnut kernels was predicted using Pearson correlation analysis and a Back Propagation Neural Network(BPNN)model.The results showed that RH had a significant effect on the quality of walnut kernels,with 65%RH being the suitable storage condition for them.According to gas chromatography-mass spectrometry(GC-MS)analysis,a total of 40,34,23 and 17 characteristic VOCs were identified in the walnut kernels stored at RH of 35%,50%,65%and 80%,respectively.Among these VOCs,hexanal,1-octen-3-ol,4,5-dimethyltetrahydrofuran-2-one and DL-pantolactone were identified as potential volatile deterioration markers(PVDMs).Based on the POV limit standard of 1.0 mmol/kg for walnut oil,the threshold concentrations of these four PVDMs were 500-1000,50-100,10-15,and 30-60μg/100g,respectively.This research provides a reference for the quality monitoring and evaluation of walnut kernels during storage. 展开更多
关键词 walnutS volatile components deterioration markers chemometrics analysis relative humidity
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Analysis of the effect of temperature and packing method on the quality and oxidative stability of walnuts in storage
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作者 Xuan Ma Chongbo Huang +3 位作者 Chang Zheng Fangyan Long Mandi Zhao Changsheng Liu 《Oil Crop Science》 2025年第3期212-222,共11页
Walnuts are rich in a variety of nutritional components.However,due to their high content of unsaturated fatty acids(UFAs),the quality of walnuts tends to decline during storage,which adversely affects the development... Walnuts are rich in a variety of nutritional components.However,due to their high content of unsaturated fatty acids(UFAs),the quality of walnuts tends to decline during storage,which adversely affects the development of the walnut industry.This study was aimed to investigate the impacts of temperature and packaging methods on the storage quality and oxidative stability of walnuts.The Wen 185 walnut variety was selected,and the physical-chemical and nutritional indexes of walnuts stored for 42 weeks under different temperatures(18℃,4℃,and room temperature)and packaging methods(vacuum light-exposed,vacuum light-proof,vacuum-ra-diation light-exposed,vacuum-radiation light-proof,nitrogen-filled light-exposed,nitrogen-filled light-proof)were measured.The results showed that low temperatures,especially18℃,in combination with vacuum lightproof packaging,could effectively suppress the increase in oxidative stability indicators such as acid value(AV)and peroxide value(PV),and maintain high retention rates of nutritional indicators like tocopherol and phytosterol.This study has elucidated that low temperatures and appropriate packaging methods play the crucial roles in maintaining the quality and oxidative stability of walnuts during storage.It has provided comprehensive and valuable data support and theoretical basis for the scientific storage of walnuts,contributing to the devel-opment of the walnut industry and the guarantee of product quality. 展开更多
关键词 walnut storage TEMPERATURE Packaging methods QUALITY Oxidative stability
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Development of Flame Retardant Composite Based on Glucose-Citric Acid-Based Resin Reinforced by Walnut Shell Powder
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作者 Zhenzhou Wang Rui Luo +5 位作者 Wenqing Yang Seng Hua Lee Wei Chen Lum Longjiang Liu Xiaojian Zhou Jun Zhang 《Journal of Renewable Materials》 2025年第6期1229-1249,共21页
Highly flame-retardant bio-based composites were prepared in this study.Firstly,glucose-citric acid(GC)resin was synthesized through the interaction of glucose and citric acid derived from agricultural and forestry so... Highly flame-retardant bio-based composites were prepared in this study.Firstly,glucose-citric acid(GC)resin was synthesized through the interaction of glucose and citric acid derived from agricultural and forestry sources.Polyvinyl alcohol(PVA)served as a toughening agent,whereas walnut shell powder(WSP)functioned as a filler in the formulation of a thermosetting bio-based GC-PVA-WSP(GCPW)composite with GC resin.The findings demonstrated that boric acid increased the limited oxygen index(LOI)value of GCPW to 33%,while simultaneously diminishing its total smoke production(TSP)by 99.9%,and achieving a flame retardant index(FRI)of 5.04.In addition,the incorporation of WSP enhanced the compressive strength of the GCPW composite to 9.15 MPa.Concurrently,the GCPW composite demonstrates excellent hydrophobic properties,with a thermal conductivity as low as 0.086 W/m·K. 展开更多
关键词 GLUCOSE citric acid walnut shell powder flame retardant bio-based composite
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Walnut peptide and ginseng Rg1 co-treatment prevents the loss of neurons and cognitive decline in mouse model with memory impairment
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作者 Junxi Fu Kuzdeuova Damira +6 位作者 Wentian Song Weijia Li Li Fang Yue Leng Chunlei Liu Dan Wu Weihong Min 《Food Science and Human Wellness》 2025年第7期2581-2594,共14页
In study,we investigated the effect of treatment with combination of walnut peptides with molecular weight<3 kDa and ginsenoside Rg1(<3 kDa+Rg1)on scopolamine-induced cognitive impairment in mice and the mechani... In study,we investigated the effect of treatment with combination of walnut peptides with molecular weight<3 kDa and ginsenoside Rg1(<3 kDa+Rg1)on scopolamine-induced cognitive impairment in mice and the mechanism of brain-derived neurotrophic factor(BDNF)/tyrosine kinase B(TrKB)/cAMP response element-binding protein(CREB)signaling pathway in PC12 cells.In behavioral experiments,<3 kDa+Rg1 treatment improved the memorizing ability of mice.Treatment with<3 kDa+Rg1 significantly regulated the function of neurotransmitters and effectively improved the morphology of the neurons determined by hematoxylin and eosin(H&E),Nissl,and Golgi staining.Additionally,immunohistochemistry showed that the<3 kDa+Rg1 treatment significantly decreased acetylcholinesterase(AChE)activity and increased choline acetyl transferase(ChAT)content in the hippocampus.The treatment upregulated vesicular acetylcholine transporter(VAChT),activated the BDNF/TrKB/CREB signaling pathway,improved the remodeling of dendritic spines,and enhanced cholinergic functions.In the scopolamine-induced PC12 cells,combination treatment increased thioredoxin-1(Trx-1)expression after administering TrKB and activated signaling pathway.The results showed combination of<3 kDa+Rg1 activated the BDNF/TrKB/CREB signaling pathway by regulating function of neurotransmitters and enhanced cholinergic function to decrease cognitive impairment. 展开更多
关键词 walnut peptide Ginsenoside Rg1 Synergistic effect Memory impairment
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基于Walnut Street修正模型的短波信道仿真算法 被引量:1
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作者 曹鹏 景渊 黄国策 《计算机科学》 CSCD 北大核心 2010年第3期91-93,共3页
传统短波信道Watterson模型只能模拟信道短期变化规律。为模拟短波信道在各种长度时间段内的变化,针对短波信道接收端信噪比统计特性,提出了一种基于信噪比重放的短波信道仿真算法。该算法以Walnut Street信道模型为基础,通过对实际观... 传统短波信道Watterson模型只能模拟信道短期变化规律。为模拟短波信道在各种长度时间段内的变化,针对短波信道接收端信噪比统计特性,提出了一种基于信噪比重放的短波信道仿真算法。该算法以Walnut Street信道模型为基础,通过对实际观测数据进行分析处理,建立接收端信噪比变化的中期和长期变化统计模型,联合Watterson模型实现信道模拟。仿真结果表明,该算法可反映实际信噪比变化规律,为短波网络仿真提供精确的信道质量模拟。 展开更多
关键词 短波 网络仿真 信噪比 walnut STREET Watterson
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Study on the Model of Excessive Staminate Catkin Thinning of Proterandrous Walnut Based on Quadratic Polynomial Regression Equation and BP Artificial Neural Network 被引量:1
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作者 王贤萍 曹贵寿 +4 位作者 杨晓华 张倩茹 李凯 李鸿雁 段泽敏 《Agricultural Science & Technology》 CAS 2015年第6期1295-1300,共6页
The excessive staminate catkin thinning (emasculation) of proterandrous walnut is an important management measure for improving yield. To improve the excessive staminate catkin thinning efficiency, the model of quad... The excessive staminate catkin thinning (emasculation) of proterandrous walnut is an important management measure for improving yield. To improve the excessive staminate catkin thinning efficiency, the model of quadratic polynomial regression equation and BP artificial neural network was developed. The effects of ethephon, gibberel in and mepiquat on shedding rate of staminate catkin of pro-terandrous walnut were investigated by modeling field test. Based on the modeling test results, the excessive staminate catkin thinning model of quadratic polynomial regression equation and BP artificial neural network was established, and it was validated by field test next year. The test data were divided into training set, vali-dation set and test set. The total 20 sets of data obtained from the modeling field test were randomly divided into training set (17) and validation set (3) by central composite design (quadric rotational regression test design), and the data obtained from the next-year field test were divided into the test set. The topological struc-ture of BP artificial neural network was 3-5-1. The results showed that the pre-diction errors of BP neural network for samples from the validation set were 1.355 0%, 0.429 1% and 0.353 8%, respectively; the difference between the predicted value by the BP neural network and validated value by field test was 2.04%, and the difference between the predicted value by the regression equation and validated value by field test was 3.12%; the prediction accuracy of BP neural network was over 1.0% higher than that of regression equation. The effective combination of quadratic polynomial stepwise regression and BP artificial neural network wil not only help to determine the effect of independent parameter but also improve the prediction accuracy. 展开更多
关键词 walnut THINNING BP artificial neural network Regression PREDICTION
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Study on Adsorption of Hg(Ⅱ) by Chinese Walnut(Juglans mandshurica Maxim.) of Biomass Material 被引量:3
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作者 于春光 杜茂安 查金苗 《Agricultural Science & Technology》 CAS 2011年第12期1869-1872,共4页
[Objective] The aim of the study was to make research on adsorption of Chinese walnut(Juglans mandshurica Maxim.) Shell(CWS) to Hg(Ⅱ) in water.[Method] Shells of Juglans mandshurica Maxim were used as biosorpti... [Objective] The aim of the study was to make research on adsorption of Chinese walnut(Juglans mandshurica Maxim.) Shell(CWS) to Hg(Ⅱ) in water.[Method] Shells of Juglans mandshurica Maxim were used as biosorption to remove Hg(Ⅱ) in water solution to explore the influence to adsorption of Hg(Ⅱ) under different conditions,like pH solution,adsorption time,and Hg(Ⅱ).[Result] The experimental results show that when absorptivity of Hg(Ⅱ) by CWS reached the highest,pH ranged within 5.0-6.0.The adsorptivity decreased as initial Hg(Ⅱ) concentrations increased.Fourier Transform Infrared Spectroscopy(FTIR) spectrum revealed some chemical groups of CWS may affect the adsorption of Hg(Ⅱ),such as hydroxyl groups,methyl groups,aromatic methoxyl groups,unconjugated carbonyl,and typical aromatic ring,etc.Adsorption equation can be concluded considering the biosorption process relationship with Langmuir and Frendrich isotherm.[Conclusion] The study found that CW could be employed as a promising biosorption to remove Hg(Ⅱ) from aqueous environments. 展开更多
关键词 BIOSORPTION Chinese walnut shell Hg(Ⅱ)ions Aqueous solution ISOTHERM
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High Yield Cultivation Techniques of Two Fine Walnut Varieties, Qingxiang and Liaohe 1 被引量:1
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作者 孙琦 王小丽 +4 位作者 刘志培 顿耀元 黄进 胡浩南 安菲 《Agricultural Science & Technology》 CAS 2017年第6期1051-1054,1057,共5页
Since the introduction of Qingxiang and Liaohe 1 in 2012, both varieties have shown characteristics of beautiful nuts appearance, high quality and high yield of nuts, strong disease resistance after six years regional... Since the introduction of Qingxiang and Liaohe 1 in 2012, both varieties have shown characteristics of beautiful nuts appearance, high quality and high yield of nuts, strong disease resistance after six years regional varieties. Comparison shows that Qingxiang has strong tree vigor, making it suitable for loose planting, needs pollination tree, bears food late and shows very stable yield performance, while Liaohe 1 has medium tree vigor, bears food early and shows stable yield performance. Based on years of regional planting tests, suggestions were proposed to the high yield cultivation techniques of walnut. 展开更多
关键词 walnut Qingxiang Liaohe 1 Cultivation techniques
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Walnut Tree Grafting Experiments in Different Areas in Yunnan Province 被引量:1
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作者 赵廷松 范志远 +8 位作者 谭凤琼 王洪艳 潘莉 邹伟烈 杜春花 刘娇 曾清贤 饶绍松 王斌 《Agricultural Science & Technology》 CAS 2017年第4期704-706,共3页
Yunnan has an area of 2.88 million hm2 walnut trees. Due to freezing in- jury and rapid growth, however, there are a lot of iron walnuts or inferior-quality walnuts ready for grafting. In five years, we conducted expe... Yunnan has an area of 2.88 million hm2 walnut trees. Due to freezing in- jury and rapid growth, however, there are a lot of iron walnuts or inferior-quality walnuts ready for grafting. In five years, we conducted experiments in Kunming (Yunnan Academy of Forestry), Gongshan County, Gucheng City, Luliang County, and Ludian County by cleft grafting, veneer grafting, bark grafting and whip grafting. The grafting approaches should be selected according to grafting requirements, characteristics, and survival rate. For example, with a low survival rate, cleft grafting can be abandoned, and the rest approaches might be chosen as per practical demands. 展开更多
关键词 YUNNAN Different areas walnut trees Grafting experiment
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Study on Technology and Formula of Walnut-Roxburgh Rose Beverage 被引量:1
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作者 邢建华 薄惠 +1 位作者 张红军 刘军伟 《Agricultural Science & Technology》 CAS 2013年第3期503-506,共4页
[Objective] The study aimed to explore technology and formula of walnut- roxburgh rose beverage. [Method] With walnut and roxburgh rose as the main raw material, technology and formula of walnut-roxburgh rose beverage... [Objective] The study aimed to explore technology and formula of walnut- roxburgh rose beverage. [Method] With walnut and roxburgh rose as the main raw material, technology and formula of walnut-roxburgh rose beverage was study by or- thogonal test. In addition, effects of emulsion stabilizers were investigated. [Result] The great emulsifying effect could be achieved by composite emulsion stabilizer at 0.40%. The orthogonal test showed that the optimum formula of walnut-roxburgh rose beverage was composed of 24% walnut milk, 16% cili juice and 12% sugar, with pH of 4.0. The product with stable organization state, pleasant sweetness and sourness may be prepared. [Conclusion] The study laid the foundation for production of walnut-roxburgh rose beverage. 展开更多
关键词 walnut Roxburgh rose BEVERAGE PROCESS FORMULA
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不同施肥模式对藏南核桃园土壤肥力与核桃产量及品质的影响
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作者 杨文胜 杨凯 +2 位作者 朱建强 吴启侠 许晓宏 《中国土壤与肥料》 北大核心 2026年第1期96-103,共8页
为提高藏南核桃产量和品质,增加当地群众收入,在有10年树龄的核桃园开展了田间培肥试验。共设置5个施肥处理,包括不施肥(对照,CK),有机肥+缓释氮肥+磷肥+钾肥一次性施用(T1),有机肥+常规氮肥+磷肥+钾肥减量施用(T2),有机肥+常规氮肥+磷... 为提高藏南核桃产量和品质,增加当地群众收入,在有10年树龄的核桃园开展了田间培肥试验。共设置5个施肥处理,包括不施肥(对照,CK),有机肥+缓释氮肥+磷肥+钾肥一次性施用(T1),有机肥+常规氮肥+磷肥+钾肥减量施用(T2),有机肥+常规氮肥+磷肥+钾肥分两次施用(T3),有机肥+常规氮肥+磷肥+钾肥分3次施用(T4)。结果表明,核桃根区土壤养分含量有明显分层现象,施肥对20~40 cm土层的土壤肥力影响较大;不同处理之间土壤的有机质、碱解氮、有效磷和速效钾含量均存在显著差异;相比CK,T2处理土壤的有机质含量提高了19.7%,T4处理的土壤碱解氮、有效磷和速效钾含量分别提高了11.8%、35.6%和18.4%;施肥对核桃叶片氮含量的影响较为显著,对核桃果实品质的提升效果有限,仅T1处理的核桃核仁中粗蛋白含量有显著提高(13.9%);所有施肥处理的单株产量比CK均有所提高,其中增产超过5%的处理有T3(6.1%)和T4(8.3%);T4处理的经济效益显著提升,增幅达10.8%。从培肥地力、提高产量和经济效益的角度看,值得推荐的施肥模式为T4处理;从提升果实品质角度,宜采用施肥模式T1处理。以上研究结果可为藏南核桃主产区增产增效和提质增效提供科学依据。 展开更多
关键词 核桃 施肥管理 产量 品质 土壤肥力
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基于SPME-GC-MS与电子鼻的藤椒核桃仁风味成分分析及货架期稳定性
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作者 唐晓华 雷舒雯 +2 位作者 李凌飞 龚加顺 付晓萍 《食品科学》 北大核心 2026年第1期185-194,共10页
为明确藤椒核桃仁的特征感官属性与关键风味物质,探究包装方式、贮藏温度对其感官品质及货架期的影响,为产品风味调控与贮藏保鲜提供理论依据,采用固相微萃取-气相色谱-质谱联用结合电子鼻技术分析风味物质,设置2种包装材料(聚对苯二甲... 为明确藤椒核桃仁的特征感官属性与关键风味物质,探究包装方式、贮藏温度对其感官品质及货架期的影响,为产品风味调控与贮藏保鲜提供理论依据,采用固相微萃取-气相色谱-质谱联用结合电子鼻技术分析风味物质,设置2种包装材料(聚对苯二甲酸乙二醇酯(polyethylene terephthalate,PET)、聚乙烯(polyethylene,PE)/铝(aluminium,AL)/PET)、3种包装方式(常压、真空、真空+脱氧),在4、25、37℃条件下开展贮藏实验,并结合动力学模型构建货架期预测模型。结果表明:藤椒核桃仁的特征感官属性为以烤香、鸡油味为核心,搭配铃兰香气与清新花草香,兼具藤椒特色辨识度,其中共鉴定出52种挥发性成分,决定该感官属性的关键物质组合为(E,Z)-2,4-癸二烯醛(相对气味活度值=100.00,主导烤香与鸡油味)、芳樟醇(赋予铃兰香)及藤椒来源的萜烯类/硫化物(强化藤椒辨识度)。贮藏对照实验显示,PE/AL/PET+真空+脱氧包装对感官属性及关键物质组成的维持效果最优,配合4℃低温贮藏时,基于过氧化值、酸价的货架期分别达164、157 d;构建的货架期预测模型相对误差低于14%,拟合度良好。综上,PE/AL/PET+真空+脱氧包装结合4℃低温,是维持藤椒核桃仁特征感官与关键风味物质的优选方法,可为其工业化品质调控提供支撑。 展开更多
关键词 藤椒 核桃仁 风味 货架期
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核桃种皮多酚类物质差异分析
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作者 崔帅帅 马梦琪 +6 位作者 丁洋洋 张洪华 虎海防 王红霞 潘志勇 张锐 郭众仲 《果树学报》 北大核心 2026年第2期323-335,共13页
【目的】探究不同核桃品种发育期种皮中单宁等多酚类物质的差异,明晰核桃种皮中单宁等多酚类物质的合成与积累规律。【方法】以新疆本地实生优系核桃兵塔1号(低单宁含量)、新疆主栽品种温185(中单宁含量)和扎343(高单宁含量)3个核桃品... 【目的】探究不同核桃品种发育期种皮中单宁等多酚类物质的差异,明晰核桃种皮中单宁等多酚类物质的合成与积累规律。【方法】以新疆本地实生优系核桃兵塔1号(低单宁含量)、新疆主栽品种温185(中单宁含量)和扎343(高单宁含量)3个核桃品种的种皮为试验材料,在关键时期对核桃种皮细胞形态进行观察,同时对单宁等酚类物质含量进行测定,并对结果进行相关性分析。【结果】核桃中单宁等多酚类物质在种皮中大量富集,单宁在核桃种皮中的积累和储存受单宁细胞的影响;不同核桃品种种皮中多酚与黄酮类物质的积累模式存在显著差异,且与单宁含量呈现出品种相关性。【结论】揭示了新疆核桃种皮的单宁积累模式,初步探究了兵塔1号单宁低积累现象中形态与物质代谢的协同机制。莽草酸代谢的分流、表儿茶素的合成效率以及黄酮物质的竞争路径是导致品种间差异的关键因素,为深入解析核桃种皮多酚代谢机制提供了形态与分子依据,为低涩味、高营养核桃品种的定向培育及加工利用提供了理论支撑。 展开更多
关键词 核桃种皮 单宁 酚类物质 高效液相色谱
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Study on Improvement of Walnut Bud Grafting Technology in the North 被引量:1
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作者 孙阳 《Agricultural Science & Technology》 CAS 2016年第5期1214-1216,共3页
[Objective] This study was conducted to change the situation of high cost in walnut grafting by reducing seedling cost through technical means.[Method] Effects of different rootstock processing methods and rootstock p... [Objective] This study was conducted to change the situation of high cost in walnut grafting by reducing seedling cost through technical means.[Method] Effects of different rootstock processing methods and rootstock pruning time on walnut growth and cost were studied by the square bud grafting method.[Result] The survival rate and cost under stumping were higher than those under no stumping,and the proportion of grafting-capable rootstocks under stumping was lower than that under no stumping by 9%.The cost differences between different rootstock time were remarkable.The cost for the stock pruning 15 d after grafting was 5 times as much as 1 d after grafting.[Conclusion] Direct grafting could achieve the effect of easy and convenient management,and the overall cost was lower though the survival rate was reduced to a limited extent.Sooner rootstock pruning resulted in a better effect.Pruning the rootstocks within 5 d after grafting not only could improve the quality of seedlings,but also could reduce the cost for seedling management. 展开更多
关键词 walnut Bud grafting Survival rate GROWTH COST
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Studies on Powder Scattering Regularities of Male Flowers of Walnut in Xinjiang
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作者 宁万军 廖康 +3 位作者 王国安 张强 刘娟 黄闽敏 《Agricultural Science & Technology》 CAS 2013年第12期1747-1749,1763,共4页
[Objective] The aim was to find out the regularities of powder scattering about walnuts' male for improving walnut yield and quality. [Method] The powder was collected by the method of gravity glass slide, and the re... [Objective] The aim was to find out the regularities of powder scattering about walnuts' male for improving walnut yield and quality. [Method] The powder was collected by the method of gravity glass slide, and the regulation of powders scattering of 'Xinxin2' and "Wen185' which were the two main cultivated varieties of walnut in Xinjiang were studied. [Result] The results showed that the male inflo- rescence powder lasted for around 10 d, and centralized scatter powder was about 4 d, when walnut male at the daily mean temperature was from 20 to 24℃. Gen- erally, the large powder shedding amount was in east, south and central position of crown, in the range of 19 to 27 ℃, and the optimal temperature of powder scatter- ing was 20 to 23 ℃. [Conclusion] The pollens scattering regularities of walnut is closely related to temperature. With a favorable temperature, powder scattering per- forms outstandingly. 展开更多
关键词 XINJIANG walnut TEMPERATURE Male inflorescence Powder scattering
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基于果实表型的核桃种质资源遗传多样性分析
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作者 冀中锐 史根生 +4 位作者 郝华正 许陶瑜 王晶 陈霖 李建 《安徽农业科学》 2026年第1期100-104,139,共6页
[目的]研究核桃种质资源果实表型多样性和变异特点,为核桃优良种质构建、新品种选育提供数据基础和理论依据。[方法]以山西农业大学经济作物研究所核桃选种圃199份丰产性较好的核桃单株为研究对象,测定其15个果实表型性状,分析各性状的... [目的]研究核桃种质资源果实表型多样性和变异特点,为核桃优良种质构建、新品种选育提供数据基础和理论依据。[方法]以山西农业大学经济作物研究所核桃选种圃199份丰产性较好的核桃单株为研究对象,测定其15个果实表型性状,分析各性状的变异系数和遗传多样性,并进行方差、相关性、主成分、聚类分析。[结果]不同核桃果实数量性状均表现出差异,变异系数为7.31%~25.89%,均值为17.59%;对199份核桃种质资源的15个表型性状进行相关性分析,各性状间存在相关性。坚果平均重是衡量坚果单果重的主要参数,与青果平均重和湿果平均重均达到极显著正相关,相关系数分别为0.820、0.828;平均仁重与坚果平均重也呈极显著正相关;出仁率与平均壳厚呈极显著负相关;出仁率与青果平均重、坚果平均重均呈极显著负相关。通过主成分分析将15个性状降维成5个主成分,其贡献率累计达到74.63%。聚类分析将199份核桃资源分为六大不同用途的育种类群。[结论]199份丰产核桃单株的果实表型性状显示出较高的遗传多样性,且各表型性状间关系较为密切;筛选到“Y-323”1份特优异品种,可作为改良大果型、单果重量大的亲本材料加以利用。 展开更多
关键词 核桃 种质资源 多样性
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核桃青皮生物炭负载腐植酸对水中四环素吸附效应
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作者 喻洁 朱晓丽 +3 位作者 张星 张子夜 柯玉鑫 张婵娟 《西北大学学报(自然科学版)》 北大核心 2026年第1期35-46,共12页
针对废水中四环素类(tetracycline,TC)有机污染物,开发高性能吸附剂材料仍是环境研究的热点问题之一。核桃青皮作为一种农业废弃物,常被随意堆放在野外,既对周边生态环境产生影响,也忽视了其潜在的应用价值。基于此,以不同热解温度制备... 针对废水中四环素类(tetracycline,TC)有机污染物,开发高性能吸附剂材料仍是环境研究的热点问题之一。核桃青皮作为一种农业废弃物,常被随意堆放在野外,既对周边生态环境产生影响,也忽视了其潜在的应用价值。基于此,以不同热解温度制备的核桃青皮生物炭(HF)为原料,通过负载腐植酸得到了3种生物炭-腐植酸复合材料HA-HF300、HA-HF500和HA-HF700,探究其对TC的吸附效应。试验结果显示,HA-HF700对TC表现出最佳的吸附性能,表征分析结果证实HA-HF700综合了2种材料的特性,具备更丰富的表面官能团和更强的芳香性,从而提高了复合材料的吸附性能。此外,HA-HF700在pH=3、材料投加量为1 g·L^(-1)时,对TC表现出最强的吸附性能,实测吸附量达到76.20 mg·g^(-1)。然而,当溶液中存在Mg^(2+)、Ca^(2+)、Na^(+)和K^(+)时,则会对HA-HF700吸附TC产生抑制作用。准二级动力学和Langmuir等温吸附模型更准确地描述了HA-HF700对TC的吸附过程。结合材料表征结果,认为HA-HF700对TC的吸附作用主要包括静电作用、氢键作用、π-πEDA相互作用和疏水作用。研究结论为废水中四环素类污染物的无害化处理提供了理论支撑。 展开更多
关键词 核桃青皮 生物炭 腐植酸 四环素 吸附
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基于CFD-DEM耦合仿真的气吸式核桃定向摆放装置的设计与试验
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作者 刘梦迪 王应彪 +2 位作者 王周梅 张超宇 李九峰 《中国油脂》 北大核心 2026年第1期122-128,共7页
为确保核桃在吸附摆放过程中的姿态固定,设计一种气吸式核桃定向摆放装置。利用CFD-DEM气固两相耦合仿真方法对核桃定向摆放的工作过程进行分析,以核桃与吸口的距离、气流速度、负压强度为考察因素,定向合格指数为评价指标,采用单因素... 为确保核桃在吸附摆放过程中的姿态固定,设计一种气吸式核桃定向摆放装置。利用CFD-DEM气固两相耦合仿真方法对核桃定向摆放的工作过程进行分析,以核桃与吸口的距离、气流速度、负压强度为考察因素,定向合格指数为评价指标,采用单因素试验和响应面试验对核桃定向摆放装置的工作参数进行仿真优化,并结合实际试验验证定向吸附核桃的可行性。结果表明:核桃能被吸起的最低气流速度为25.5 m/s,最小负压强度为-93.6 kPa;影响定向合格指数的因素依次为气流速度、核桃与吸口的距离、负压强度;通过仿真优化和实际试验验证得到气吸式核桃定向摆放装置的最优工作参数为核桃与吸口的距离4 mm、气流速度27 m/s、负压强度-98 kPa,此时平均定向吸附成功率为95%。综上,气吸式核桃定向摆放装置满足核桃定向吸附摆放生产要求。 展开更多
关键词 核桃 气吸式 定向摆放 CFD-DEM
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基于点云建模的核桃树振动参数优化与试验
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作者 崔王斌 周宏平 +3 位作者 张洋 王艳艳 许林云 范高鸣 《林业科学》 北大核心 2026年第2期186-203,共18页
【目的】探究不同尺寸核桃树受迫振动时的响应情况,解决核桃振动采收过程中效率低下、果实采净率低等问题。【方法】利用地面三维激光扫描仪采集核桃树点云数据,对采集到的树体点云数据进行预处理后提取树木骨架,采用NX软件对核桃树进... 【目的】探究不同尺寸核桃树受迫振动时的响应情况,解决核桃振动采收过程中效率低下、果实采净率低等问题。【方法】利用地面三维激光扫描仪采集核桃树点云数据,对采集到的树体点云数据进行预处理后提取树木骨架,采用NX软件对核桃树进行三维拟合重建,建立不同尺寸参数的核桃树三维模型。通过实测频谱对核桃树材料特性参数进行修正,实际与仿真共同出现的共振频率中最大相对误差仅为0.22%,确保三维模型的准确性。应用Ansys对核桃树树体三维模型进行谐响应分析,探究激振频率、激振力、激振高度3个参数对振动加速度的影响,分析不同尺寸核桃树在不同频率下的位移和加速度响应情况;结合挂果枝位移、加速度响应和谐响应云图上核桃树的响应情况进一步探究不同尺寸核桃树的适宜采收频率。【结果】核桃树的加速度响应峰值随直径、高度和冠幅增加而降低,较高树体和大冠幅对高频振动的响应较弱,表明树体的几何特性显著影响其振动特性。对核桃树振动采收参数进行响应面分析并优化,得到核桃树振动采收的最优振动参数组合,在最优振动参数激振下核桃采收率均在90%以上,表明该振动频率参数可为核桃树振动采收装置工作时的参数设置提供参考。【结论】根据本研究描述的核桃树建模方法可以实现对核桃树细小侧枝的重建,且重建出来的整树模型具有更为真实的生长形态特征;不同直径、不同高度、不同冠幅的核桃树振动响应不同,适宜振动频率范围为10~20 Hz,可根据树形结构参数进一步确定该频率范围。 展开更多
关键词 核桃收获 振动采收 有限元分析 振动响应 响应面分析 激振频率优化
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New Walnut Cultivar “Ludian-dama No.1”
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作者 赵廷松 范志远 +6 位作者 曾清贤 邹伟烈 潘莉 刘娇 杜春花 谭凤琼 王洪艳 《Agricultural Science & Technology》 CAS 2017年第2期329-331,352,共4页
"Ludian-dama No.1" is a late frost-avoiding new walnut varieties bred from seedling in cold region of Yunnan Province in the northeast of Yunnan Ludian County. The new variety had oval nut, circled base of fruit and... "Ludian-dama No.1" is a late frost-avoiding new walnut varieties bred from seedling in cold region of Yunnan Province in the northeast of Yunnan Ludian County. The new variety had oval nut, circled base of fruit and lightly sharp top fruits with the average single fruit weight of 14.44 g, and the shell engraved a large shallow with wrinkle surface. The suture line was protuberant and tight, and the shell thickness was 0.89 mm. The inner fold wall had paper quality, and diaphragm was well-developed. The kernel rate was 51.2% with rough fat content of 74.67%, protein content of 18.5%. And it was easy to peel off the kernel, which was large and full with delicate taste. "Ludian-dama No.1" passed the examination and approval of the Forest Variety Approval Committee of Yunnan Province in December, 2014. 展开更多
关键词 New walnut variety "Ludian-dama No. 1"
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