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热带作物译丛 1987年第4期 4-9页

作者： j.l.jacob 范思伟

本文论述了参与胶乳再生的主要调节机制及其调节位于树皮中“橡胶工厂”的活性。了解影响胶乳再生的参数有助手正确判断在一定条件下胶树的生产能力,从而有助于合理采胶。

关键词：乳管细胞胶乳胞液橡胶胶树 NADH 弹性体黄色体多聚异戊二烯

HYDRUS-2D simulations of water movement in a drip irrigation system under soilless substrate

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International journal of Agricultural and Biological Engineering 2022年第3期15卷 210-216页

作者： lei Geng li li Wei li Chengfei Yang Fanjia Meng Key laboratory of Agricultural Information Acquisition Technology Ministry of Agriculture and Rural AffairsChina Agricultural UniversityBeijing100083China Key laboratory of Smart Agriculture System Integration Ministry of EducationChina Agricultural UniversityBeijing 100083Chin

A comprehensive understanding of the distribution and water movement of the substrate in root areas is crucial to the design and management of drip irrigation systems,which is a significant step to maximizing crop water use efficiency by understanding the hydrodynamics in soilless *** this study,an improved HYDRUS-2D model by the dynamic root growth model was used to simulate water movement under the condition of drip irrigation and the water uptake process of the root,and then,compared with the observed *** water content under drip irrigation was also measured with the calibrated ECH20-EC5 *** situation of substrate water movement was analyzed under the conditions of different depths,different initial water content,and different irrigation *** substrate water movement under different drip irrigation conditions was *** results showed that incorporating the defined initial and boundary conditions and the hydraulic characteristics of the substrate into the model enabled HYDRUS model to predict the movement and position of water in unsaturated porous media by solving Richards *** drip irrigation,the substrate wetting body was approximately a quarter ellipse,and the water would continue to move to the area where the wetting front did not reach within 1 h after *** simulation results of the improved HYDRUS-2D model agreed well with those observed by the ECH2O-EC5 sensors,and the model could provide a basis for precision irrigation of soilless substrate culture under drip irrigation.

关键词： drip irrigation HYDRUS-2D substrate water movement soilless substrate

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Chemical Evolution of the Continental Terminal Shallow Aquifer in the South of Coastal Sedimentary Basin of Benin (West-Africa) Using Multivariate Factor Analysis

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journal of Water Resource and Protection 2015年第6期7卷 496-515页

作者： Abdoukarim Alassane Rim Trabelsi léonce F. Dovonon Diane j. Odeloui Moussa Boukari Kamel Zouari Daouda Mama laboratoire d’Hydrologie Appliquée Faculté des Sciences et Techniques Université d’Abomey-Calavi Abomey-Calavi Bénin laboratoire de Radio-Analyse et Environnement Ecole Nationale d’Ingénieurs de Sfax Université de Sfax Sfax Tunisie laboratoire d’Etude et de Recherche en Chimie Appliquée Ecole Polytechnique d’Abomey-Calavi Université d'Abomey-Calavi Abomey-Calavi Bénin

In southern Benin, where population is growing and water demand for domestic activities is increasing, water balance assessment constitutes a serious concern about sustainability of water resources. Major ions have been employed with statistical methods to identify geochemical processes controlling groundwater quality. Multivariate statistical analysis (principal component analysis “PCA” and hierarchical cluster analysis “HCA”) revealed the main sources of groundwater mineralization. According to the hydrochemical data and the methods of treatment, groundwater mineralization in the investigated aquifer is caused by four main processes: 1) mixing with Nokoué lake and Porto-Novo lagoon salt water causing salinity to increase in the southern part of the aquifer;2) anthropogenic activities;3) cation exchange process;and 4) soil CO2 diffusion providing a large proportion of bicarbonates.

关键词： Hydrogeochemical Process Pollution Shallow Groundwater Continental Terminal Benin

Seasonal Patterns of Nitrogen and Phosphorus in the litter and Soil Surface of Transitional Amazon Cerrado Forest, Brazil

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journal of Environmental Science and Engineering 2011年第1期5卷 5-14页

作者： j. de S. Nogueira l. Sanches O.B. Pinto-junior E.D. de Almeida Department of Physics Federal University of Mato Grosso Av. Fernando Correa da Costa 2367 Boa Esperanva Cuiaba MT 78060-900 Brazil Department of Sanitary and Environmental Engineering Federal University of Mato Grosso Av. Fernando Correa da Costa 2367 Boa Esperanca Cuiaba MT 78060-900 Brazil Department of Chemistry Federal Institute of Technological Education of Mato Grosso Rua Professora Zulmira Canavarros 95 Cuiabca MT 78005-200 Brazil

Measurements of litter production, and the surface litter pool were made over a 1 year period in a tropical transitional forest near Sinop, Mato Grosso Brazil with the aim of quantifying the seasonal variation of nitrogen and phosphorus in the litter and the annual contribution of nutrients to the soil. Average annual litterfall （＋95% confidence interval （CI）） was 8.20 ***^-1 year^-1 and forest floor litter mass was 58.63 ton＇hal. Nitrogen and phosphorus in the forest floor litter mass was highest during the dry and dry-wet season, being 38% higher than in the wet and wet-dry season. Seasonal variation in the litter and concentration of nutrients was explained by seasonal variations in the climate, for example in the precipition and soil humidity. Average annual nitrogen and phosphorus concentrations in the forest floor mass were 17.24 ***^-1 and 16.46 ***^-1, respectively. The more significant forest floor mass fraction for returning soil nutrients was the leaves. The concentration of nutrients was higher in the soil superficial layer （at depths between 0-5 cm） than at depths between 30-70 cm, approximately 83% and 93% for total nitrogen and available phosphorus, respectively.

关键词： Tropical forest litterpool nutrient cycling litterfall

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碱金属阴离子化合物(续)

丽水学院学报 1990年第S1期15卷 90-96页

作者： j.l.Dye 牟松龄张丰台州师专杭州大学

3 热力学的思考碱金属阴离子可在氨中存在是根据热力学论证提出的。我们寻找碱金属阴离子的盐类(我们把它叫做“碱化物”)也是根据对它们稳定性的热力学预测,在寻找适合的金属,溶剂和络合剂方面仍然以稳定常数的估算作指导。关于其它... 详细信息

3 热力学的思考碱金属阴离子可在氨中存在是根据热力学论证提出的。我们寻找碱金属阴离子的盐类(我们把它叫做“碱化物”)也是根据对它们稳定性的热力学预测,在寻找适合的金属,溶剂和络合剂方面仍然以稳定常数的估算作指导。关于其它金属如碱土金属阴离子的可能性问题也已提出。热力学容易说明象Ca^-这样的阴离子在溶液中是不可能存在的,而Au^-阴离子在热力学上是相当稳定的。本节将提供一些有关的热力学论据。有些予言可以作得相当准确,而另一些予言的把握性要小得多。

关键词：稳定常数溶剂化电子可能性问题离子化合物节将热力学数据配位层溶剂化自由能络合剂原子间距

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CTMP制浆工艺及其应用的发展概况(上)

国外造纸 1989年第4期8卷 3-8页

作者：罗松年 j.l.Valade 章杰

一、前言 CTMP(化学热磨机械浆)是一类高得率化学机械浆。它的得率一般在90%以上。在七十年代中期,瑞典造纸界为了降低TMP的磨浆能耗和改善它的质量,在TMP制浆工艺预热木片之前,对木片先进行温和的化学处理,研制成功了CTMP。

关键词： CTMP 制浆工艺化学热磨机械浆

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癌的免疫学

世界科学译刊 1979年第5期 5-12页

作者： l.j.Old 曹慧琴

癌细胞虽有“异体”标记,但它们能逃避免疫系统的破坏。现正努力查明癌细胞如何能逃避免疫系统的破坏及利用免疫反应来治疗癌症。

关键词：肿瘤免疫癌症免疫增强剂卡介苗免疫反应结核菌苗菌苗免疫性免疫学基础医学抗原性特异抗原

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摩擦减振器

智慧轨道交通 1979年第1期 22-28页

作者： j.l.Koffman 施治才

二轴货车和转向架货车走行系统的设计的焦点又一次集中在摩擦减振器上。最初的走行系统设计方案是采用叠板弹簧,结合使用单吊杆或双吊杆,以在垂直面和水平面提供适当的阻尼。应用圆弹簧,特别是因其静挠度超过30毫米,要求有附加的阻尼。... 详细信息

二轴货车和转向架货车走行系统的设计的焦点又一次集中在摩擦减振器上。最初的走行系统设计方案是采用叠板弹簧,结合使用单吊杆或双吊杆,以在垂直面和水平面提供适当的阻尼。应用圆弹簧,特别是因其静挠度超过30毫米,要求有附加的阻尼。故常摩擦减振器首先在机车和电动车组车辆上获得应用。在英国,常摩擦减振器最先用在Class71型2000千瓦电力机车上。根据考夫曼的提议,以与机车上使用的相似的方案用于伦敦中区ClassAM310电动车组的动车转向架上,其

关键词：摩擦减振器货车货运车辆转向装置转向架点头振动空车

Polyamine Metabolism of the Cotton Flower and Its Sub-tending leaf under Water-Deficit Stress in the Field

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American journal of Plant Sciences 2013年第5期4卷 84-91页

作者： D. A. loka D. M. Oosterhuis j. D. Mattice B. l. McMichael Department of Energy The Politecnico di Milano Milano Italy Department of Tecnologie e Progettazione Università di Bergamo Bergamo Italy.

Polyamines, putrescine, spermidine and spermine are low molecular weight polycations implicated in flowering and seed set and plants’ responses under adverse environmental conditions. Research in other crops has shown that polyamine metabolism is greatly affected by water-deficit stress, however, no information exists on cotton (Gossypium hirsutum l.). A field study was conducted in 2011 in two contrasting locations (Fayetteville, AR, and lubbock, TX) in order to investigate the effect of water-deficit stress during flowering on polyamine metabolism of the cotton flower and its subtending leaf. Treatments consisted of control (well watered) and water-stress (irrigation withheld for two weeks at the onset of flowering) in a split plot design. First day white flowers and their subtending leaves were collected at the end of each week of the stress period for determination of polyamine concentrations. Water-deficit stress resulted in significant increases in PUT and SPD levels of pistils and leaves compared to the control. However, pistil and leaf SPM content significantly increased under drought conditions in one location and remained unaltered in the other one. leaf and pistil polyamine metabolism of cotton appeared to be greatly affected by limited water supply, however further research is needed to elucidate the ways polyamines can be used to increase cotton drought tolerance.

关键词： Cotton Polyamines Reproductive Stage Water-Deficit Stress

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胶料混炼程度的测定

世界橡胶工业 1985年第5期 83-88页

作者： j.l.den otter 程林妹

橡胶与其它材料混炼时,产品的质量及混炼所消耗的能量主要取决于胶料的混炼程度。为了测定炭黑在丁苯橡胶中的混炼度,橡胶和塑料研究协会(TNO)对四种不同的方法进行了试验。这四种方法是小角X射线散射法、未硫化混炼胶的动态机械测定法... 详细信息

橡胶与其它材料混炼时,产品的质量及混炼所消耗的能量主要取决于胶料的混炼程度。为了测定炭黑在丁苯橡胶中的混炼度,橡胶和塑料研究协会(TNO)对四种不同的方法进行了试验。这四种方法是小角X射线散射法、未硫化混炼胶的动态机械测定法、扫描电子显微镜法及电阻测定法。虽然四种方法之间的相关性良好,但是最后一种方法的灵敏度最高

关键词：混炼过程胶料炭黑补强剂高耐磨炉黑炉法炭黑橡胶弹性体丁苯程度导电性小角