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101.
Knop M Pacyna S Voloshchuk N Kant S Müllenborn C Steiner U Kirchmair M Scherer HW Schulz M 《Journal of chemical ecology》2007,33(2):225-237
Benzoxazolinone detoxification is similar in plants grown under sulfur deficiency conditions and in control plants grown with
an optimal S supply. However, when S-deficient plants were treated with metolachlor before benzoxazolin-2(3H)-one (BOA) incubation,
detoxification was reduced, as indicated by a lower accumulation of the detoxification products BOA-6-O-glucoside and glucoside carbamate and by a loss of BOA-6-OH glucosyltransfease activity. Root colonizing microorganisms and
the endophytic fungus Fusarium verticillioides participated in benzoxazolinone detoxification by converting the compound to 2-acetamidophenol (AAP) or O-hydroxyphenyl malonamic acid (OHPMA), a process accompanied by the appearance of phenoxazinone. Maize roots, however, absorbed
AAP and OHPMA only in traces. Absorbed traces of OHPMA stimulated maize radicle growth, and traces of AAP stimulated cress.
Phenoxazinone inhibited the growth of cress radicles at concentrations higher than 500 μM, whereas maize radicles were hardly
affected. F. verticillioides did not convert benzoxazolinone to any known microbial degradation product when the medium of maize seedlings was inoculated
with the fungus under sterile condition. Plant–fungus interactions seem to be important in plant survival of allelopathic
attacks. This study points to a complicated network of allelopathic interactions that are influenced by biotic and abiotic
factors, including herbicides. 相似文献
102.
In order to investigate the mechanisms of coke desulfurization by blowing additional gas into coking chamber during pyrolysis process, some experiments were conducted to study the effects of some factors on the distribution of sulfur in coke. These factors include pyrolysis temperatures, the kinds of the blowing gases and the diameters of coking chamber. It was found that sulfur was mainly released at the range of 300–600 °C. Under this temperature range, the sulfur content in coke can be reduced by 0.05–0.06% by blowing N2, CO or CH4, and by 0.14% by blowing H2 at a space velocity of 1.2 mm/s compared with the absolute sulfur content of 0.92% in the case without gas feeding. Obviously, H2 is more effective on sulfur removal than N2, CO or CH4. The total, organic and inorganic sulfur contents in coke increase with increasing the diameter of coking chamber under identical pyrolysis conditions. Both organic and inorganic sulfur contents in coke increase regularly from the center to brim at identical height of a coke column for all the cases. In addition, the organic and inorganic sulfur contents at the cranny surface are higher than those in interior at the same sampling position. X-ray photoelectron spectroscopy (XPS) analyses suggest that the main contributions to the increase of inorganic and organic sulfur contents are due to the formation of negative bivalent sulfur and thiophenic compounds, respectively. 相似文献
103.
本文报导了三-三苯基膦氧化钴(I)与过量的异硫氰酸苯酯反应,依据快原子轰击质谱(FAB-MS),证实生成物的结构为四员钴杂环配合物。该配合物不稳定,容易脱硫,生成苯基异腈钴(Ⅱ)配合物。 相似文献
104.
杂多酸脱硫制硫新工艺 总被引:9,自引:0,他引:9
对几种不同种类和来源的杂多酸进行了实验筛选,对杂多酸溶液的氧化还原电位进行了实验测定。研究表明,杂多酸脱硫在热力学上是可行的,但实际过程中单一的杂多酸体系再生过程非常缓慢,难以实用;钒类化合物能够加速杂多酸的再生,两种钒类化合物对再生过程的催化性能相近。在实验条件下,HPA分子中的Mo(Ⅵ)至少会转变为Mo(Ⅳ),很大可能会转变为Mo(Ⅲ)。 相似文献
105.
结合潜山高含硫井的实际情况,对高含硫井井身结构、井眼轨迹进行了优化设计,对钻井液进行了优选,结合工程实际情况选择了相应级别的防硫井口装置和套管及主要附件,满足了高含硫井钻井施工安全、快速的要求。技术实用性强,为今后该类井在实际生产中的发展与应用提供了宝贵的经验。 相似文献
106.
Styrene-based deproteinized natural rubber (SNR) latex was synthesized by in situ polymerization. Three pre-vulcanization systems [conventional-cured (CV), semi-efficient-cured (Semi-EV), and efficient-cured (EV)] were studied in terms of tensile and adhesion properties. Good tensile properties were observed for CV and EV SNR. The Semi-EV SNR showed the best adhesion properties based on the good anchorage performance in all substrate pairings (polystyrene–polystyrene, polystyrene–rubber, and rubber–rubber). The pH modification on SNR latex via KOH addition has beneficial effects of removing protein layers, resulting in more styrene grafting sites in the rubber molecules. Consequently, the tensile and adhesion properties of the SNR are improved as more styrene polymers are grafted onto the rubber matrix. Semi-EV SNR with pH 12 has superior adhesive performance; hence, it is suitable for use as a pressure-sensitive adhesive. 相似文献
107.
108.
水泥中硫的高频红外分析方法研究 总被引:1,自引:0,他引:1
采用高频红外吸收法测定了水泥中硫的含量,并对样品作测定前的预处理(物理处理),在测定中选用复合型助熔剂,解决了高频感应炉中因顶吹氧气流的作用而导致的样品喷溅问题。该法可准确测定水泥中0.001%~5%的硫,回收率为98.6%~102.5%,RSD为0.78%~1.35%。 相似文献
109.
110.