Results 41 to 50 of about 5,405 (176)
The Construction and Utilization of on-line Normal-Phase Liquid Chromatography × Reversed-Phase Liquid Chromatography System and the Study on the Chemical Constituents of Toad Skin [PDF]
, 2017 本文旨在构建一个正相色谱（NPLC）与反相色谱（RPLC）联用的在线二维分析与制备液相色谱系统。首先，通过设计一个新型的高温蒸发辅助吸附（TEAA）接口，解决了流动相不兼容问题，实现了正相色谱与反相色谱的在线联用。该接口可以使正相溶剂在高温下迅速蒸发，将样品富集在正相富集柱上，继而利用洗脱液洗脱富集的样品，稀释后富集在反相富集柱上，进一步在反相色谱中得到分离。进而，以蟾皮醇提物为样品溶液，对TEAA接口的一系列参数进行了优化，包括正相富集的温度、真空度，正相富集柱的洗脱时间和重生时间。其次 ...
李加福
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Multiple global change factors alter the scaling of nitrogen to phosphorus in alpine plants
Functional Ecology, Volume 39, Issue 8, Page 2044-2055, August 2025.Read the free Plain Language Summary for this article on the Journal blog. Abstract The stoichiometry and allometry of nitrogen (N) and phosphorus (P) reflect nutrient absorption and dynamic allocation by plants, and can be regulated by global change factors (e.g. nitrogen enrichment, climate warming and altered precipitation). Yet, how multiple global
Jiapu Li +10 more
wiley +1 more source
Preliminary study on quorum sensing system in Novosphingobium pentaromativorans US6-1 for BaP biodegradation [PDF]
, 2017 一直以来，多环芳烃（PAHs）污染治理已经成为环境科学关注的热点问题。微生物修复因具有强降解能力和对环境友好等特点，被认为是环境中多环芳烃去除的主要途径。近些年来，人们在筛选高效降解菌和探究多环芳烃代谢路径等方面都取得了进展，然而微生物在菌群水平上是如何应对多环芳烃所带来的胁迫压力目前尚不清楚。本论文以一株能广谱和高效地降解2至5环PAHs的革兰氏阴性细菌—新鞘氨醇杆菌US6-1（NovosphingobiumpentaromativoransUS6-1）为研究对象，利用显微镜观察 ...
詹清
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Composition and structure of extraction residue of direct coal liquefaction residue and recycle of active phase of iron catalyst [PDF]
In order to solve the problem of iron source supply for large-scale direct liquefaction catalyst, and meanwhile realize the harmless separated-utilization of extraction residue from coal liquefaction, this paper conducted a research on the recovery of ...
Dao LI +5 more
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Functional Ecology, Volume 39, Issue 5, Page 1274-1287, May 2025.Read the free Plain Language Summary for this article on the Journal blog. Abstract Interactions between plants and soil microorganisms in the rhizosphere are vital for maintaining the nutrient cycle and stability of terrestrial ecosystems. Nitrogen, closely related to carbon (C) cycling and ecosystem productivity, undergoes transformation by soil ...
Ru Wang +9 more
wiley +1 more source
Functional Ecology, Volume 39, Issue 2, Page 621-634, February 2025.Read the free Plain Language Summary for this article on the Journal blog. Abstract Tropical forests are generally characterized by high species diversity and low soil phosphorus (P) availability. Although tropical plants have evolved adaptations to low soil P availability, we know relatively little about the strategies of different groups of species ...
Yingxu Fan +11 more
wiley +1 more source
Shuitu Baochi Xuebao, 2011 以沂蒙山区的棕壤为例,利用野外原位模拟降雨试验,在分析比较5种典型覆被土壤结构稳定性的基础上,探讨不同土地覆被土壤结构稳定性对侵蚀泥沙全氮(N)、全磷(P)流失的影响。结果表明,土壤结构稳定性以山楂园和侧柏林较好,金银花和荒草地次之,花生地最差。不同土地覆被类型泥沙全N、全P流失特征差异明显,泥沙流失率与其全N、全P流失参量间具有显著的相关关系。土壤结构稳定性通过调节侵蚀产沙进而影响泥沙中N、P的流失特征,山楂园等土壤结构稳定性较好,侵蚀过程中更多地选择性搬运粘粒及精细颗粒,致使泥沙全N ...
于兴修, 马骞, 刘前进, 张含玉
doaj
, 2007 沉水植物对重金属的积累净化和受害机理研究主要集中在4个方面:(1)沉水植物对重金属(包括放射性物质)的吸收、积累和净化作用;(2)沉水植物对重金属的抗性强弱和机制;(3)沉水植物用于监测水体的重金属污染:(4)沉水植物的重金属胁迫机制,包括重金属对植物形态和显微结构的损伤,对植物抗氧化酶系统的影响,对植物的叶绿素、蛋白质以及光合与呼吸作用等生理生化指标的影响,植物对重金属的吸附和转运动力学 ...
吴振斌, 靳萍, 马剑敏
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Shuitu Baochi Xuebao, 2005 田间沟垄微型集雨结合覆盖技术有效地利用了膜垄的集水和沟覆盖的蓄水保墒功能,改变了降雨的时空分布,使降雨集中富集在种植沟中,显著地提高了降水的利用效率,特别是小雨的利用率。研究结果表明:土垄的平均集水效率为7% ,而垄上覆膜后集水效率为87% ,膜垄能产生径流的最小降雨量为0 8mm。田间沟垄微型集雨结合覆盖技术能提高土壤贮水量,增加玉米的产量。垄上覆膜结合沟覆盖处理玉米产量比平地增加2 339～5 2 97kg/hm2 (44 %～14 3% ) ,水分利用效率基本都在2kg/m3 以上。
李小雁 张瑞玲
doaj
, 2019 新兴的光动力抗菌疗法是无创激发式治疗手段,主要利用近红外光作为光源,激活富集在病灶部位的光敏剂并产生活性氧自由基,最终实现对目标病菌的杀伤作用。相对比与传统的抗生素治疗,光动力抗菌疗法具有创伤性小,副作用低,不易产生耐药性等优点,在抗菌治疗方面有很大临床应用前景。随着生物材料与纳米医学技术的发展,小分子光敏剂纳米功能化后其生物兼容性和生物安全性得到优化,量子产率和病灶部位富集率显著提升,为其临床应用提供了新思路。本文结合小分子光敏剂纳米化策略方法实例 ...
任恩, 刘刚, 庞鑫, 张昌, 李蕾
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