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741.
蚕豆对铯的吸收蓄积及亚细胞分布研究 总被引:1,自引:0,他引:1
采用改良水培法培养蚕豆幼苗至2片真叶,置于含铯(ρ(Cs+)8.24(CK)~200 mg·L~(-1))的营养液中处理7 d、14 d、21 d后取样。采用差速离心法分离亚细胞组分,采用原子吸收分光光度法测定根、茎、叶及各亚细胞组分的Cs+含量,分析蚕豆幼苗对Cs+的吸收蓄积及亚细胞分布特点,研究蚕豆对Cs+的富集转运特征及耐受机理。结果显示:蚕豆3种器官对Cs+的蓄积量为根叶茎,根对Cs+的蓄积量占总量的65.13%~83.17%,最高(ρ(Cs+)200 mg·L~(-1)时)达到518.40 mg·kg~(-1)FW(7 d)、1 949.74 mg·kg~(-1)FW(14 d)和3 614.03 mg·kg~(-1)FW(21 d);蚕豆根、茎、叶中Cs+的亚细胞分布主要集中在细胞壁和可溶性组分中,Cs+相对含量分别达到75.84%~99.06%(根)、79.06%~100%(茎)、82.95%~100%(叶);细胞核、前质体、叶绿体和线粒体等细胞器仅含少量的Cs+(25%)。结果表明,蚕豆根、茎、叶细胞主要通过阻滞作用,将Cs+结合固定在细胞壁,并将进入细胞质基质的一部分Cs+转运到液泡内,暂时或"永久性"存贮,有效降低了细胞器、胞质溶胶(cytosol)及内含物中的Cs+含量,极大地减缓了Cs+对细胞器的功能性损伤,这是短期内蚕豆未表现出明显中毒症状的原因,也是蚕豆耐受Cs+胁迫的重要机理之一。 相似文献
742.
The rapid development of the fluorinated pesticide industry has produced a large amount of fluorine-containing hazardous waste, especially inorganic fluoride-containing waste(IFCW). A two-step process, including extraction and recovery, was developed to recover fluorine as synthetic cryolite from IFCW produced by the pesticide industry. The optimum conditions for extraction were found to be a temperature of 75℃, an initial p H(p Hi) of 12, a4-hr incubation time and a liquid-to-solid ratio of 40 m L/g; these conditions resulted in a fluorine extraction ratio of 99.0%. The effects of p H and the F/Al molar ratio on fluorine recovery and the compositional, mineralogical and morphological characteristics of the cryolite products were investigated. Field-emission scanning electron microscopy of recovered precipitates showed changes in morphology with the F/Al molar ratio. Coupling Fourier transform and infrared spectroscopy, X-ray diffraction indicated that the formation of Al F3-6was restricted as increasing p H. Both the amount of fluorine recovered and the quality of the cryolite were optimized at initial p H = 3 and a F/Al molar ratio 5.75. This study proposed a reliable and environmentally friendly method for the treatment of fluoridecontaining wastes, which could be suitable for industrial applications. 相似文献
743.
Haoran Dong Guangming Zeng Chang Zhang Jie Liang Kito Ahmad Piao Xu Xiaoxiao He Mingyong Lai 《环境科学学报(英文版)》2015
This study investigated the interaction between Cu2 + and nano zero-valent iron (NZVI) coated with three types of stabilizers (i.e., polyacrylic acid [PAA], Tween-20 and starch) by examining the Cu2 + uptake, colloidal stability and mobility of surface-modified NZVI (SM-NZVI) in the presence of Cu2 +. The uptake of Cu2 + by SM-NZVI and the colloidal stability of the Cu-bearing SM-NZVI were examined in batch tests. The results showed that NZVI coated with different modifiers exhibited different affinities for Cu2 +, which resulted in varying colloidal stability of different SM-NZVI in the presence of Cu2 +. The presence of Cu2 + exerted a slight influence on the aggregation and settling of NZVI modified with PAA or Tween-20. However, the presence of Cu2 + caused significant aggregation and sedimentation of starch-modified NZVI, which is due to Cu2 + complexation with the starch molecules coated on the surface of the particles. Column experiments were conducted to investigate the co-transport of Cu2 + in association with SM-NZVI in water-saturated quartz sand. It was presumed that a physical straining mechanism accounted for the retention of Cu-bearing SM-NZVI in the porous media. Moreover, the enhanced aggregation of SM-NZVI in the presence of Cu2 + may be contributing to this straining effect. 相似文献
744.
吴昊张城瑜倪珊珊罗彬彬王梦鸽魏雯敏陈裕坤赖钟雄 《应用与环境生物学报》2022,(4):1057-1065
植物光敏色素作用因子(phytochrome interacting factor,PIF)是广泛分布于植物体内的一种转录因子,在植物的生长发育方面有着重要的作用.基于香蕉基因组数据,对香蕉MaPIF基因家族进行基因组鉴定,采用生物信息学分析方法对其进行命名,分析理化性质、蛋白质结构、基因结构、启动子顺势作用元件以及构建系统进化树;分析PIF家族在不同激素处理下的表达情况.结果显示,香蕉MaPIF家族有7个成员,均含有高度保守的bHLH结构域;编码区长度在1 116-2001bp之间,至少包含5个内含子,且大部分位于细胞外;进化树结果可以发现与拟南芥、水稻以及玉米PIF的亲缘关系较近;顺式作用元件预测结果显示,MaPIF上存在多种与激素和光相关的响应元件.qRT-PCR结果显示,MaPIF3-1、MaPIF4、MaPIF4-1在生长素(IAA)、赤霉素(GA)、生长素抑制剂(NPA)处理中均有显著表达,除此之外,所有成员在脱落酸(ABA)处理下均有明显表达.本研究表明MaPIF在香蕉生长发育中激素调控有重要作用.(图7表3参45) 相似文献
745.
Yu Xia Xuyang Zhang Miao Zhang Liming Chen Xiaotong Tang Yuhong Sun Xiang Li 《Frontiers of Environmental Science & Engineering》2022,16(11):145
746.
Yu Chunmu Chen Xiaojuan Li Ning Chen Jieming Yao Liang Zhou Yu Lu Kaihong Lai Yiqi Lai Xiangyu 《Environmental science and pollution research international》2022,29(54):81383-81395
Environmental Science and Pollution Research - Large amount of municipal sludge is difficult to handle; its resource utilization is an effective measure. In this study, the municipal sludge from... 相似文献
747.
Zhang Nan Lai Hui Ying Gautam Archana De Kwek Darien Yu Dong Yibing Wang Qiang Ng Kee Woei 《Journal of Polymers and the Environment》2022,30(3):1045-1054
Journal of Polymers and the Environment - Hair contains about 80% keratins and 1–3% melanin packaged in melanosomes. Both of these are high-value and functional raw materials that have... 相似文献
748.
3-Dehydroquinic acid dehydrase/shikimate dehydrogenase (DHD/SDH) is the only bifunctional enzyme in the shikimic acid pathway. It can catalyze the generation of shikimic acid and gallic acid. To investigate the expression and regulation patterns of DHD/SDH in tea, we aimed to determine (1) the miRNA-mediated cleavage of DHD/SDH involved in the shikimic acid pathway, (2) the expression pattern of miRNA and their targets, and (3) the expression pattern of three DHD/SDH genes in tea plant (Camellia sinensis) with different hormone treatments via online prediction, RLM-RACE, and qPCR. Based on the miRNAs obtained, we identified four miRNAs that regulated CsDHD/SDH in tea. CsDHD/SDH2 was targeted by miR5180b, miR1510b-5p, and miR24; CsDHD/SDH3 was targeted by miR868-5p. We also found that CsDHD/SDH2 and CsDHD/SDH3 have a similar expression pattern under different hormone treatments, and they were synergistic with each other. CsDHD/SDH1 exhibited an expression pattern opposite to that of the other two homologues, and increased expression of CsDHD/SDH1 reduced the expression of the other two genes. © 2018 Science Press. All rights reserved. 相似文献
749.
凋落物分解是湿地生态系统中碳和养分循环的关键过程.对比叶片凋落物和细根的分解速率,有助于阐明水分变化条件下不同凋落物类型对湿地碳循环的相对贡献,提高人们对不同有机碳源分解驱动机制的理解.以安徽省升金湖湿地典型湿生植物——陌上菅(Carex thunbergii)为研究对象,采用分解袋法进行凋落物分解试验,分析叶片凋落物和细根在不同土壤水分含量(30%、50%和70%)下的分解动态.结果表明:①经过5个月的分解,在30%、50%和70%的土壤水分含量下,陌上菅的细根质量残留率分别为46.7%、58.1%和60.1%,叶片凋落物的质量残留率分别为37.9%、31.6%、33.9%.②在30%、50%和70%的土壤水分含量下,陌上菅的细根分解速率常数分别为1.78、1.27、1.12,叶片凋落物的分解速率常数分别为2.56、2.94、2.54,且它们之间存在显著性差异(P < 0.05).③细根的分解速率与土壤水分含量之间呈负相关(P < 0.001),而叶片凋落物的分解速率与土壤水分含量呈正相关(P=0.01).④根据重复测量方差分析结果可知,凋落物分解受凋落物类型、分解时间及二者交互作用的影响,且凋落物类型是主导因素.分别对细根和叶片凋落物的质量损失进行重复测量方差分析,发现在细根的分解过程中,土壤水分含量是主要影响因素,而在叶片凋落物分解过程中,分解时间是主导因素.研究显示,相同土壤水分含量下,叶片凋落物的分解速率比细根快;湿地水位变化条件下,土壤水分含量对细根和叶片凋落物分解具有不同的影响,土壤水分含量的增加促进了叶片凋落物的分解,但对细根的分解产生了抑制作用. 相似文献
750.
Fan Lu Tianyu Hu Shunyan Wei Liming Shao Pinjing He 《Frontiers of Environmental Science & Engineering》2021,15(3):45