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1.
Majid Vaezzadeh Ehsan Noruzifar Ghanati Faezeh Mohsen Salehkotahi Reza Mehdian 《Journal of magnetism and magnetic materials》2006
Experimental results of applying a steady magnetic field (20 and 30 mT) on agricultural plants reveal that their growth is more than that of control plants. Considering that these plants have ferritin cells, and each ferritin cell has 4500 Fe atoms, it is obvious that they have an outstanding role in the plants’ growth. As the last spin magnetic moment (SMM) of the Fe atom posed to an external magnetic field (EMF), the composition of SMM and EMF create an oscillator in the system. Then we have a moment of force on ferritin cells. This oscillator exerts its energy, then damps and finally locates in the field direction. The relaxed energy increased the internal temperature (i.e., the effective temperature of the magnetic spin system of plant) so that it is situated in a proper temperature for growing. This phenomenon (temperature increasing) occurs in the initial minutes of applying the magnetic field. So it depends on the number of times of locating the plant in magnetic field in a day (n). If this number (n) passes the critical value, the plant reaches a burning temperature and growth is perturbed. In this paper, the plant growth rate and critical temperature in a steady magnetic field were investigated and formulated theoretically. An innovative result in this research is as follows: if a plant's environment was in the dormant temperature, we could increase the internal temperature of the plant by applying a magnetic field n times in a day (for growth). 相似文献
2.
茄子组织生物微电极在儿茶酚测定中表现出了较高的生物催化活性,而对抗坏血酸测定则为稳态响应,这表明该电极能有效地消除抗坏血酸的干扰。该电极的灵敏度高,重现性好,对多巴胺测定的线性范围为5.8×10~(-6)~6.5×10~(-4)mol/L,检出下限为:2.9×10~(-6)mol/L。 相似文献
3.
4.
Sannomiya M Rodrigues CM Coelho RG dos Santos LC Hiruma-Lima CA Souza Brito AR Vilegas W 《Journal of chromatography. A》2004,1035(1):47-51
The methanolic extract of the leaves of the medicinal plant Byrsonima crassa (Malpighiaceae) contain flavonoids with antioxidant activity. They were separated in a preparative scale using high-speed counter-current chromatography. The optimum solvent system used was composed of a mixture of ethyl acetate-n-propanol-water (140:8:80 (v/v/v)) and led to a successful separation between monoglucosilated flavonoids (quercetin-3-O-alpha-L-arabinoside, quercetin-3-O-beta-D-galactoside) and the biflavonoid amentoflavone in only 3.5 h. The purities of quercetin-3-O-alpha-L-arabinoside (95 mg), quercetin-3-O-beta-D-galactoside (16 mg) and the biflavonoid amentoflavone (114 mg) were all isolated at purity over 95%. Identification was performed by 1H NMR, 13C NMR and UV analyses. 相似文献
5.
6.
Summary The aim of this investigation was to obtain qualitative and quantitative profiles of the flavonoid and biflavonoid composition
of six cypress species—Cupressus funebris L.,Cupressus sempervirens L.,Cupressus glabra L.,Cupressus arizonica L.,Cupressus goveniana L., andCupressus lusitanica L. HPLC-diode-array detection (DAD), HPLC-MS, and HPTLC were used to identify the individual compounds. A chromatographic
method was optimized for identification and quantification of the main flavonoid glycosides and biflavonoids. The flavonoids
identified and calibrated were: rutin, quercetin glucoside, quercetin rhamnoside, and kaempferol 3-O-rhamnoside. The biflavonoids identified and calibrated were: cupressuflavone, amentoflavone, robustaflavone, hinokiflavone,
methylrobustaflavone, methylamentoflavone, and dimethylcupressuflavone. 相似文献
7.
植物样品中单宁的微波溶出快速测定法研究 总被引:16,自引:0,他引:16
研究了利用微波代替一般的沸水浴处理试样的方法。对不同植物样品中单宁的浸提测定,与常规方法做了对照,并讨论了微波功率、时间、酸度等因素对测定结果的影响。研究表明,此法可大大地缩短测定时间,提高测定效率,节省人力、物力,不污染环境,便于大批量样品的测定,相对标准偏差≤1.4%,测定结果较为满意。为植物样品中单宁的测定,提供了一个快速、简便、准确的分析方法,并可借鉴于其它样品的测定。 相似文献
8.
We report enantioselective synthesis of phyllanthurinolactone (1), a leaf-closing substance of Phyllanthus urinaria L., and its analogs with sugars other than d-glucose. Structure-activity relationship study using them revealed that the structure of the sugar moiety did not affect their bioactivity at all. This result is very important for the development of molecular probes based on the structure of 1. 相似文献
9.
10.
Anders Thygesen Jette Oddershede Hans Lilholt Anne Belinda Thomsen Kenny Ståhl 《Cellulose (London, England)》2005,12(6):563-576
A comparative study of cellulose crystallinity based on the sample crystallinity and the cellulose content in plant fibres
was performed for samples of different origin. Strong acid hydrolysis was found superior to agricultural fibre analysis and
comprehensive plant fibre analysis for a consistent determination of the cellulose content. Crystallinity determinations were
based on X-ray powder diffraction methods using side-loaded samples in reflection (Bragg-Brentano) mode. Rietveld refinements
based on the recently published crystal structure of cellulose Iβ followed by integration of the crystalline and amorphous
(background) parts were performed. This was shown to be straightforward to use and in many ways advantageous to traditional
crystallinity determinations using the Segal or the Ruland–Vonk methods. The determined cellulose crystallinities were 90–100 g/100 g
cellulose in plant-based fibres and 60–70 g/100 g cellulose in wood based fibres. These findings are significant in relation
to strong fibre composites and bio-ethanol production. 相似文献