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单片叶制作清香型铁观音的工艺与品质研究 被引量:1
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作者 周炎花 谢杰全 +2 位作者 郭雅玲 杨双旭 肖腾香 《中国茶叶》 2022年第11期18-23,共6页
为开发清香型铁观音“单叶茶”新产品,以铁观音茶树品种的单片鲜叶为原料,按清香型铁观音的加工工艺,设置正交试验,并对茶样进行感官审评和生化成分分析。结果表明,最佳加工工艺为晒青减重率5%、摇青4次、炒青温度300℃。所制茶样外形... 为开发清香型铁观音“单叶茶”新产品,以铁观音茶树品种的单片鲜叶为原料,按清香型铁观音的加工工艺,设置正交试验,并对茶样进行感官审评和生化成分分析。结果表明,最佳加工工艺为晒青减重率5%、摇青4次、炒青温度300℃。所制茶样外形圆结重实,色泽翠绿润,香气清高持久,滋味鲜醇甘爽;水浸出物、茶多酚、游离氨基酸、可溶性糖的含量均较高,而咖啡碱的含量较低。研究结果为清香型铁观音“单叶茶”加工提供了技术参考。 展开更多
关键词 单片叶 清香型 铁观音 工艺 品质
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直升机主动控制技术发展研究 被引量:1
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作者 杨开天 《航空科学技术》 2006年第5期21-25,共5页
介绍了直升机主动控制技术的发展历程,分析了高阶谐波控制、结构响应主动控制、单片桨叶控制、地面/空中共振主动控制和电控/智能材料主动控制的特点。
关键词 高阶谐波 结构响应 地面/空中共振 电控/智能材料
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Analysis on the Phenophase Characteristics of Zhengdan958 and Xianyu335 in North of Huanghuaihai Region
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作者 陈淑萍 卜俊周 +5 位作者 岳海旺 彭海成 宋聪敏 茜晓哲 张玉兰 谢俊良 《Agricultural Science & Technology》 CAS 2014年第4期585-588,708,共5页
[Objective] The study is aimed to timely grasp the growth and develop- ment process of summer maize and comprehensively evaluate the impact of envi- ronmental factors on the growth and development of maize in north Hu... [Objective] The study is aimed to timely grasp the growth and develop- ment process of summer maize and comprehensively evaluate the impact of envi- ronmental factors on the growth and development of maize in north Huanguaihai re- gion. [Method] The phenophase, leaf unfolding rate, grain filling rate and yield char- acteristics of Zhengdan 958 and Xianyu 335 were analyzed at N 37°53′, E115°42′. [Result] The summer corn Zhengdan 958 and Xianyu335 emerged in 6 days after sowing with the growing period of 111 d, grain-filling stage lasting 66 days, and the leaf unfolding rate and grain filling rate were accelerated with the increase of tem- perature. In the last 6 d before harvest (October 5-11), Zhengdan 958 and Xi- anyu335 contributed to the yield by 6.61% and 4.20%, respectively. The two crops a year cropping system made it hard for the summer maize to achieve maturing harvest in north Huanghuaihai region. [Conclusion] The maize production could be significantly improved through selecting early maturing varieties, early sowing, timely late harvest, ensuring maize effective accumulated temperature and sufficient grout- ing time after pollination. 展开更多
关键词 Zhengdan958 Xianyu335 PHENOPHASE Leaf unfolding rate Filling rate
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Study on the ultraviolet-visible spectral feature of tobacco leaves by pattern recognition
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作者 RUAN Chun-sheng XU Chang-liang +5 位作者 ZHANG Ge FAN Jing LI Yu-zhong WANG Xiao-xia FANG Li CHEN Sui-yun 《Journal of Life Sciences》 2009年第9期34-42,53,共10页
In order to differentiate regions, varieties, and parts of tobacco leaves, two pattern recognition methods through pattern classification modeling were developed based on the comprehensive information of ultraviolet-v... In order to differentiate regions, varieties, and parts of tobacco leaves, two pattern recognition methods through pattern classification modeling were developed based on the comprehensive information of ultraviolet-visible spectroscopy (UV-VIS) by employing one-way analysis of variance (ANOVA1) and wave range random combination (WRRC) technology from MATLAB. This proposed classification method has never been reported previously and the instrument and operation for this method is much more convenient and efficient than previous reported classification methods. The result of this paper demonstrated that the spectral features extracted by ANOVAI and WRRC methods could be used to differentiate tobacco leaves with different patterns. The ANOVAI method had a training recognition rate range of 75.00-87.50%,4 and a validation recognition rate range of 57.14-100%. The WRRC method had a training recognition rate range of 75.00-94.12% and a validation recognition rate range of 66.67-100%. The ANOVAI method is more convenient and efficient in model developing, while the WRRC method utilizes fewer model variables and is more robust. 展开更多
关键词 Nicotiana tabacum ultraviolet-visible spectroscopy (UV-VIS) pattern recognition spectral feature DIFFERENTIATION
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Phenol Compounds of Blackberry (Rubus caucasicus Focke and Rubus anatolicus L.) Fruit and Leaf
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作者 Mzla Dlasamldze Maia Vanidze Indira Djafaridze Elene Qamadadze Aleko Kalandia 《Journal of Chemistry and Chemical Engineering》 2013年第6期539-546,共8页
It is investigated of the effect of plant blackberry (Rubus caucasicus Focke and Rubus anatolicus L.) flower, fruit and leaf content of phenol compounds qualitative and quantitative HPLC (high-pressure liquid chrom... It is investigated of the effect of plant blackberry (Rubus caucasicus Focke and Rubus anatolicus L.) flower, fruit and leaf content of phenol compounds qualitative and quantitative HPLC (high-pressure liquid chromatography) and spectral methods. HPLC analysis revealed that the fetus was a major of both species, cyanidin-3-glucoside, and it reached full maturity period 1,493.54 ± 44.81 and 1,636.58 ±49.10 mg/kg (cyanidin-3-O-glucoside chloride equivalents) calculated on the dry weight. In mature fetus flavonols is (884.8±26.54)-(979.0 ± 29.37) mg/kg (rutin equivalents) calculated on the dry weight, catechins (21.2± 0.64)-(25.01 ± 0.7537) mg/kg ((+) catechin equivalents) calculated on the dry weight, leucoantocyanins (48.8 ±1.46)-(52.1± 1.56) mg/kg (cyanidin equivalents) calculated on the dry weight. In this regard, there was a slight difference between the species. Most of the leaf flavonols were presented 3.7 ± 0.111 g/kg. Phenol carbonic acids--the leaves of 13.4 ± 0.402 mg/kg calculated on the dry weight, the flowers of 8.8± 0.264 mg/kg, calculated on the dry weight. Full maturity period, the number of phenol carbonic acids cent is (3,707.8 ± 111.23)-(4,287.5 ± 128.63) mg/kg, (caffeic acid equivalents) is calculated on the dry weight of the unit. Also been determined HPLC following the method of compounds is: cyanidin-3-glucoside, quercetin-3-rutinoside, quercetin-3-glucoside, ellagic acid, gallic acid and chlorogenic acid. 展开更多
关键词 Blackberry (Rubus caucasicus Focke and Rubus anatolicus L.) anthocyanins phenolics FLAVONOIDS HPLC.
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为害陕西眉县猕猴桃的小绿叶蝉族害虫学名更正
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作者 王益梅 徐业 +1 位作者 李建军 秦道正 《应用昆虫学报》 CAS CSCD 北大核心 2022年第1期203-212,共10页
【目的】明确为害陕西眉县猕猴桃园的小绿叶蝉族害虫学名和形态特征,对首次发现的优势种多型现象进行描述。【方法】采用网捕法采集小绿叶蝉族成虫,用相机拍摄相关生态照片;在体视解剖镜下观察标本形态特征,进行分类鉴定,对主要形态特... 【目的】明确为害陕西眉县猕猴桃园的小绿叶蝉族害虫学名和形态特征,对首次发现的优势种多型现象进行描述。【方法】采用网捕法采集小绿叶蝉族成虫,用相机拍摄相关生态照片;在体视解剖镜下观察标本形态特征,进行分类鉴定,对主要形态特征进行拍照。【结果】为害陕西眉县猕猴桃的小绿叶蝉族害虫有单片膜瓣叶蝉Membranacea unijugata Qin&Zhang,2011、广道小绿叶蝉Empoasca(Empoasca)hiromichi(Matsumura,1931)和松田小绿叶蝉Empoasca(Empoasca)matsudai(Dworakowska,1972);本研究共采集小绿叶蝉族标本685头,其中单片膜瓣叶蝉有深色型(均为雄性)88头,浅色型472头(包括雄性13头、雌性459头),该种标本数占所采标本总数的81.75%,广道小绿叶蝉和松田小绿叶蝉的标本数量分别占标本总数的17.66%和0.58%。【结论】为害陕西猕猴桃的小绿叶蝉族害虫优势种是单片膜瓣叶蝉,其成虫存在多型现象。我国猕猴桃的其他小绿叶蝉族害虫学名有待进一步调查明确。 展开更多
关键词 猕猴桃 小绿蝉族 膜瓣 多型现象
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基于IBC方法的旋翼BVI噪声主动控制机理 被引量:7
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作者 倪同兵 招启军 马砾 《航空学报》 EI CAS CSCD 北大核心 2017年第7期120-132,共13页
为揭示单片桨叶控制(IBC)主动控制技术抑制旋翼桨-涡干扰(BVI)噪声的降噪机理,建立了一套基于CFD/CSD/FW-H_pds方程的综合噪声分析方法。旋翼桨-涡干扰噪声与旋翼桨叶载荷特性、气动变形以及旋翼桨尖涡结构等密切相关,为有效模拟旋翼桨... 为揭示单片桨叶控制(IBC)主动控制技术抑制旋翼桨-涡干扰(BVI)噪声的降噪机理,建立了一套基于CFD/CSD/FW-H_pds方程的综合噪声分析方法。旋翼桨-涡干扰噪声与旋翼桨叶载荷特性、气动变形以及旋翼桨尖涡结构等密切相关,为有效模拟旋翼桨叶的载荷特性及桨尖涡结构,将Navier-Stokes方程作为前飞流场的主控方程,空间离散上采用三阶MUSCL插值格式与通量差分裂Roe格式相结合;时间方向上采用双时间法,使用隐式LU-SGS格式在伪时间方向上进行推进;湍流模型采用对分离流动具有较好捕捉能力的Spalart-Allmaras模型。为提高旋翼桨叶弹性变形运动的模拟精度,建立了基于Hamilton变分原理的CSD模型,并与高精度的CFD求解器结合,发展了适合旋翼桨叶变形及载荷特性模拟的流固耦合分析方法。在CFD/CSD耦合方法分析流场基础上,使用可穿透空间积分面的FW-H_pds方法对旋翼气动噪声特性进行计算。首先,对流场及噪声数值方法进行验证;然后,着重针对UH-60A旋翼的斜下降飞行状态,分别对有/无IBC噪声主动控制条件下的旋翼BVI气动噪声特性进行了模拟,相位角、幅值和频率等不同控制参数的影响对比分析结果表明:IBC主动控制减小了前行侧桨叶表面尤其是桨叶尖部的负压峰值,降低了桨-涡干扰发生位置附近的桨叶气动载荷;同时主动控制后的桨尖涡集中程度变弱,并且增加了桨叶与桨尖涡之间的相遇距离,从而显著降低了桨-涡干扰噪声;选取合理的相位角、幅值和频率等主动控制参数组合,BVI噪声降低可达5~7dB。 展开更多
关键词 旋翼 桨-涡干扰(BVI)噪声 噪声主动控制 NAVIER-STOKES方程 FW-H_pds方法 CFD/CSD耦合方法 控制(IBC)
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Design and Optimization of a Single Stage Centrifugal Compressor for a Solar Dish-Brayton System 被引量:5
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作者 Yongsheng Wang Kai Wang +3 位作者 Zhiting Tong Feng Lin Chaoqun Nie Abraham Engeda 《Journal of Thermal Science》 SCIE EI CAS CSCD 2013年第5期404-412,共9页
According to the requirements of a solar dish-Brayton system,a centrifugal compressor stage with a minimum total pressure ratio of 5,an adiabatic efficiency above 75% and a surge margin more than 12% needs to be desig... According to the requirements of a solar dish-Brayton system,a centrifugal compressor stage with a minimum total pressure ratio of 5,an adiabatic efficiency above 75% and a surge margin more than 12% needs to be designed.A single stage,which consists of impeller,radial vaned diffuser,90° crossover and two rows of axial stators,was chosen to satisfy this system.To achieve the stage performance,an impeller with a 6:1 total pressure ratio and an adiabatic efficiency of 90% was designed and its preliminary geometry came from an in-house one-dimensional program.Radial vaned diffuser was applied downstream of the impeller.Two rows of axial stators after 90° crossover were added to guide the flow into axial direction.Since jet-wake flow,shockwave and boundary layer separation coexisted in the impeller-diffuser region,optimization on the radius ratio of radial diffuser vane inlet to impeller exit,diffuser vane inlet blade angle and number of diffuser vanes was carried out at design point.Finally,an optimized centrifugal compressor stage fulfilled the high expectations and presented proper performance.Numerical simulation showed that at design point the stage adiabatic efficiency was 79.93% and the total pressure ratio was 5.6.The surge margin was 15%.The performance map including 80%,90% and 100% design speed was also presented. 展开更多
关键词 Single Stage Centrifugal Compressor Design OPTIMIZATION
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Effects of leaf age,elevation and light conditions on photosynthesis and leaf traits in saplings of two evergreen conifers,Abies veitchii and A.mariesii 被引量:1
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作者 Rina Suzuki Koichi Takahashi 《Journal of Plant Ecology》 SCIE CSCD 2020年第4期460-469,共10页
Aims Subalpine coniferous species are distributed over a wide range of elevations in which they must contend with stressful conditions,such as high elevations and extended periods of darkness.Two evergreen coniferous ... Aims Subalpine coniferous species are distributed over a wide range of elevations in which they must contend with stressful conditions,such as high elevations and extended periods of darkness.Two evergreen coniferous species,Abies veitchii and Abies mariesii,dominate at low and high elevations,respectively,in the subalpine zone,central Japan.The aim of this study is to examine the effects of leaf age,elevation and light conditions on photosynthetic rates through changes in morphological and physiological leaf traits in the two species.Methods We here examined effects of leaf age,elevation and light conditions on photosynthesis,and leaf traits in A.veitchii and A.mariesii.Saplings of the two conifers were sampled in the understory and canopy gaps at their lower(1600 m)and upper(2300 m)distribution limits.Important Findings The two species showed similar responses to leaf age and different responses to elevation and light conditions in photosynthesis and leaf traits.The maximum photosynthetic rate of A.veitchii is correlated negatively with leaf mass per area(LMA)and non-structural carbohydrate(NSC)concentration.LMA increased at high elevations in the two species,whereas NSC concentrations increased only in A.veitchii.Therefore,the maximum photosynthetic rate of A.veitchii decreased at high elevations.Furthermore,maximum photosynthetic rates correlate positively with nitrogen concentration in both species.In the understory,leaf nitrogen concentrations decreased and increased in A.veitchii and A.mariesii,respectively.LMA decreased and the chlorophyll-to-nitrogen ratio increased in understory conditions only for A.mariesii,suggesting it has a higher light-capture efficiency in dark conditions than does A.veitchii.This study concluded that A.mariesii has more shade-tolerant photosynthetic and leaf traits and its photosynthetic rate is less affected by elevation compared with A.veitchii,allowing A.mariesii to survive in the understory and to dominate at high elevations. 展开更多
关键词 leaf chlorophyll leaf mass per area leaf nitrogen non-structural carbohydrate concentration stable carbon–isotope ratio
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